Revision history for Verilator

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* Verilator 4.038 2020-07-11

**    Versions 4.038 and 4.040 are planned to be the final versions that will
      support pre-C++11 compilers. Please move to C++11 or newer compilers.

***   Support VPI access to parameters and localparam. [Ludwig Rogiers]

***   Support parsing (not elaboration, yet) of UVM.

****  Add new UNSUPPORTED error code to replace most previous Unsupported: messages.

****  With --bbox-unsup continue parsing on many (not all) UVM constructs.

****  Support for-loop increments with commas.

****  Support $swrite with arbitrary arguments.

****  Support $writememb (#2450). [Fan Shupei]

****  Fix OS X, Free BSD, and -m32 portability issues. [Geza Lore]

****  Fix to flush FST trace on termination due to $stop or assertion failure.

****  Fix part select error when multipling by power-of-two (#2413). [Conor McCullough]

****  Fix division exception (#2460) [Kuoping Hsu]


* Verilator 4.036 2020-06-06

**    OPT_FAST is now -Os by default. See the BENCHMARKING & OPTIMIZATION part
      of the manual if you experience issues with compilation speed.

***   Configure now enables SystemC if it is installed as a system headers,
      e.g. with 'apt-get install systemc-dev'.

***   Add --waiver-output flag that writes a verilator config file (.vlt) with
      waivers to the warnings emitted during a Verilator run.

***   Support verilator_coverage --write-info for lcov HTML reports.
      Line Coverage now tracks all statement lines, not just branch lines.

***   --output-split is now on by default. VM_PARALLEL_BUILDS is set by
      default iff the --output-split caused an actual file split to occur.
      --output-split-cfuncs and --output-split-ctrace now default to the
      value of --output-split. These changes should improve build times of
      medium and large designs with default options. User makefiles may
      require changes.

***   The run-time library is now compiled with -Os by default. (#2369, #2373)

****  Support multi channel descriptor I/O (#2190) [Stephen Henry]

****  Support $countbits. (#2287) [Yossi Nivin]

****  Support $isunbounded and parameter $. (#2104)

****  Support unpacked array .sum and .product.

****  Support prefix/postfix increment/decrement. (#2223) [Maciej Sobkowski]

****  Fix FST tracing of little bit endian signals. [Geza Lore]

****  Fix +: and -: on unpacked arrays. (#2304) [engr248]

****  Fix $isunknown with constant Z's.

****  Fix queues and dynamic array wide ops. (#2352) [Vassilis Papaefstathiou]


* Verilator 4.034 2020-05-03

**    Add simplistic class support with many restrictions, see manual. (#377)

**    Support IEEE time units and time precisions. (#234)
      Includes `timescale, $printtimescale, $timeformat.
      VL_TIME_MULTIPLIER, VL_TIME_PRECISION, VL_TIME_UNIT have been removed
      and the time precision must now match the SystemC time precision. To
      get closer behavior to older versions, use e.g. --timescale-override
      "1ps/1ps".

**    Add --build to call make automatically. (#2249) [Yutetsu TAKATSUKASA]

**    Configuring with ccache present now defaults to using it; see OBJCACHE.

**    Fix DPI import/export to be standard compliant. (#2236) [Geza Lore]

**    Add --trace-threads for general multithreaded tracing. (#2269) [Geza Lore]

***   Add --flatten for use with --xml-only. (#2270) [James Hanlon]

****  Greatly improve FST/VCD dump performance (#2244) (#2246) (#2250) (#2257) [Geza Lore]

****  Support $ferror, and $fflush without arguments. (#1638)

****  Support event data type (with some restrictions).

****  Support $root. (#2150) [Keyi Zhang]

****  Add error if use SystemC 2.2 and earlier (pre-2011) as is deprecated.

****  Fix build of fast path tracing code to use OPT_FAST. (#2245) [Geza Lore]

****  Fix arrayed instances connecting to slices. (#2263) [Don/engr248]

****  Fix error on unpacked connecting to packed. (#2288) [Joseph Shaker]

****  Fix logical not optimization with empty begin. (#2291) [Baltazar Ortiz]

****  Fix reduction OR on wide data, broke in v4.026. (#2300) [Jack Koenig]

****  Fix clock enables with bit-extends. (#2299) [Marco Widmer]

****  Fix MacOs Homebrew by removing default LIBS. (#2298) [Ryan Clarke]


* Verilator 4.032 2020-04-04

***   Add column numbers to errors and warnings.

***   Add GCC 9-style line number prefix when showing source text for errors.

***   Add setting VM_PARALLEL_BUILDS=1 when using --output-split. (#2185)

***   Change --quiet-exit to also suppress 'Exiting due to N errors'.

****  Suppress REALCVT for whole real numbers.

****  Support split_var in vlt files. (#2219) [Marco Widmer]

****  Fix parameter type redeclaring a type. (#2195) [hdzhangdoc]

****  Fix VCD open with empty filename. (#2198) [Julius Baxter]

****  Fix packages as enum base types. (#2202) [Driss Hafdi]

****  Fix duplicate typedefs in generate for. (#2205) [hdzhangdoc]

****  Fix MinW portability. (#2114) [Sean Cross]

****  Fix assertions with unique case inside. (#2199) [hdzhangdoc]

****  Fix implicit conversion of floats to wide integers.


* Verilator 4.030 2020-03-08

**    Add split_var metacomment to assist UNOPTFLAT fixes. (#2066) [Yutetsu TAKATSUKASA]

**    Add support for $dumpfile and $dumpvars. (#2126) [Alexander Grobman]

**    Add support for dynamic arrays. (#379)

***   Add +verilator+noassert flag to disable assertion checking. [Tobias Wölfel]

***   Add check for assertOn for asserts. (#2162) [Tobias Wölfel]

***   Add --structs-packed for forward compatibility.

***   Fix genblk naming with directly nested generate blocks. (#2176) [Alexander Grobman]

****  Implement $displayb/o/h, $writeb/o/h, etc. (#1637)

****  Use gcc -Os in examples instead of -O2 for better average performance.

****  Fix undeclared VL_SHIFTR_WWQ. (#2114) [Alex Solomatnikov]


* Verilator 4.028 2020-02-08

**    Support attributes (public, isolate_assignments, etc.) in configuration files.

**    Add -match to lint_off to waive warnings. [Philipp Wagner]

***   Link Verilator binary partially statically. (#2146) [Geza Lore]

***   Verilation speed improvements (#2133) (#2138) [Geza Lore]

***   Support libgoogle-perftools-dev's libtcmalloc if available. (#2137) [Geza Lore]

***   Support $readmem/$writemem with assoc arrarys. (#2100) [agrobman]

****  Support type(expression) operator and $typename. (#1650)

****  Support left justified $display. (#2101) [Pieter Kapsenberg]

****  Support string character access via indexing.

****  Support enum.next(k) with constant k > 1. (#2125) [Tobias Rosenkranz]

****  Support parameter access from arrays of interfaces. (#2155) [Todd Strader]

****  Add parameter values in XML. #2110. [Pieter Kapsenberg]

****  Add loc column location in XML (replaces fl). (#2122) [Pieter Kapsenberg]

****  Add error on misused define. [Topa Tota]

****  Add parameter to set maximum signal width. (#2082) [Øyvind Harboe]

****  Add warning on genvar in normal for loop. (#2143) [yurivict]

****  Fix VPI scope naming for public modules. [Nandu Raj]

****  Fix FST tracing of enums inside structs. [fsiegle]

****  Fix WIDTH warning on </<= of narrower value. (#2141) [agrobman]

****  Fix OpenSolaris issues. (#2154) [brancoliticus]

****  Fix gated clocks under --protect-lib. (#2169) [Todd Strader]


* Verilator 4.026 2020-01-11

**    Docker images are now available for Verilator releases.

***   Support bounded queues.

***   Support implication operator "|->" in assertions. (#2069) [Peter Monsson]

***   Support string compare, ato*, etc methods. (#1606) [Yutetsu TAKATSUKASA]

****  Support immediate cover statements.

****  Ignore `uselib to end-of-line. (#1634) [Frederic Antonin]

****  Update FST trace API for better performance.

****  Add vpiTimeUnit and allow to specify time as string. (#1636) [Stefan Wallentowitz]

****  Add error when `resetall inside module (IEEE 2017-22.3).

****  Add cleaner error on version control conflicts in sources.

****  Fix little endian cell ranges. (#1631) [Julien Margetts]

****  Fix queue issues (#1641) (#1643) [Peter Monsson, Stefan Wallentowitz]

****  Fix strcasecmp for windows. (#1651) [Kuba Ober]

****  Fix disable iff in assertions. Closes #1404. [Peter Monsson]

****  Fix huge case statement performance. Closes #1644. [Julien Margetts]

****  Fix tracing -1 index arrays. Closes #2090. [Yutetsu Takatsukasa]

****  Fix expand optimization slowing --lint-only. Closes #2091. [Thomas Watts]

****  Fix %{number}s with strings. #2093. [agrobman]

****  Fix shebang breaking some shells. Closes #2067. [zdave]


* Verilator 4.024 2019-12-08

**    Support associative arrays (excluding [*] and pattern assignments). (#544)

**    Support queues (excluding {} notation and pattern assignments). (#545)

***   Add +verilator+error+limit to see more assertion errors. [Peter Monsson]

***   Support string.toupper and string.tolower.

***   Support $rewind and $ungetc.

***   Support shortreal as real, with a SHORTREAL warning.

****  Add -Wpedantic and -Wno-context for compliance testing.

****  Add error on redefining preprocessor directives. [Piotr Binkowski]

****  Support $value$plusargs float and shorts. (#1592) (#1619) [Garrett Smith]

****  Fix gate lvalue optimization error. (#831) [Jonathon Donaldson, Driss Hafdi]

****  Fix color assertion on empty if. (#1604) [Andrew Holme]

****  Fix for loop missing initializer. (#1605) [Andrew Holme]

****  Fix hang on concat error. (#1608) [Bogdan Vukobratovic]

****  Fix VPI timed callbacks to be one-shot, pull5. [Matthew Ballance]

****  Fix // in filenames. (#1610) [Peter Nelson]

****  Fix $display("%p") to be closer to IEEE.

****  Fix labels on functions with returns. (#1614) [Mitch Hayenga]

****  Fix false unused message on __Vemumtab. (#2061) [Tobias Rosenkranz]

****  Fix assertion on dotted parameter arrayed function. (#1620) [Rich Porter]

****  Fix interface reference tracing. (#1595) [Todd Strader]

****  Fix error on unpacked concatenations. (#1627) [Driss Hafdi]


* Verilator 4.022 2019-11-10

**    Add --protect-lib. (#1490) [Todd Strader]

**    Add cmake support. (#1363) [Patrick Stewart]

***   Examples have been renamed.

***   Add --protect-ids to obscure information in objects. (#1521) [Todd Strader]

***   Add --trace-coverage.

***   Add --xml-output.

***   Support multithreading on Windows. [Patrick Stewart]

***   Suppress 'command failed' on normal errors.

***   Support some unpacked arrays in parameters. (#1315) [Marshal Qiao]

***   Add interface port visibility in traces. (#1594) [Todd Strader]

****  Increase case duplicate/incomplete to 16 bit tables. (#1545) [Yossi Nivin]

****  Support quoted arguments in -f files. (#1535) [Yves Mathieu]

****  Optimize modulus by power-of-two constants, and masked conditionals.

****  Fix detecting missing reg types. (#1570) [Jacko Dirks]

****  Fix multithreaded yield behavior when no work. [Patrick Stewart]

****  Fix bad-syntax crashes. (#1548, #1550-#1553, #1557-#1560, #1563,
      #1573-#1577, #1579, #1582-#1591) [Eric Rippey]

****  Fix false CMPCONST/UNSIGNED warnings on "inside". (#1581) [Mitch Hayenga]


* Verilator 4.020 2019-10-06

***   Add --public-flat-rw. (#1511) [Stefan Wallentowitz]

***   Support $fseek, $ftell, $frewind. (#1496) [Howard Su]

***   Support vpiModule. (#1469) [Stefan Wallentowitz]

****  Make Syms file honor --output-split-cfuncs. (#1499) [Todd Strader]

****  Fix make test with no VERILATOR_ROOT. (#1494) [Ahmed El-Mahmoudy]

****  Fix error on multidimensional cells. (#1505) [Anderson Ignacio Da Silva]

****  Fix config_rev revision detection on old versions.

****  Fix false warning on backward indexing. (#1507) [Hao Shi]

****  Fix vpiType accessor. (#1509) (#1510) [Stefan Wallentowitz]

****  Fix ugly error on interface misuse. (#1525) [Bogdan Vukobratovic]

****  Fix misc bad-syntax crashes. (#1529) (#1530) (#1531) (#1532) (#1533) [Eric Rippey]

****  Fix case statements with strings. (#1536) [Philipp Wagner]

****  Fix some coverage lost when multithreaded. (#2151)


* Verilator 4.018 2019-08-29

**    When showing an error, show source code and offer suggestions of replacements.

**    When showing an error, show the instance location. (#1305) [Todd Strader]

***   Add --rr. (#1481) [Todd Strader]

***   Change MULTITOP to warning to help linting, see manual.

***   Add XSim support to driver.pl. (#1493) [Todd Strader]

****  Show included-from filenames in warnings. (#1439) [Todd Strader]

****  Fix elaboration time errors. (#1429) [Udi Finkelstein]

****  Fix not reporting some duplicate signals/ports. (#1462) [Peter Gerst]

****  Fix not in array context on non-power-of-two slices. (#2027) [Yu Sheng Lin]

****  Fix system compile flags injection. [Gianfranco Costamagna]

****  Fix enum values not being sized based on parent. (#1442) [Dan Petrisko]

****  Fix internal error on gate optimization of assign. (#1475) [Oyvind Harboe]

****  Add --dpi-hdr-only. (#1491) [Todd Strader]


* Verilator 4.016 2019-06-16

***   Add --quiet-exit. (#1436) [Todd Strader]

****  Error continuation lines no longer have %Error prefix.

****  Support logical equivalence operator <->.

****  Support VerilatedFstC set_time_unit. (#1433) [Pieter Kapsenberg]

****  Support deferred assertions. (#1449) [Charles Eddleston]

****  Mark infrequently called functions with GCC cold attribute.

****  Fix sign-compare warning in verilated.cpp. (#1437) [Sergey Kvachonok]

****  Fix fault on $realtime with %t. (#1443) [Julien Margetts]

****  Fix $display with string without %s. (#1441) [Denis Rystsov]

****  Fix parameter function string returns. (#1441) [Denis Rystsov]

****  Fix invalid XML output due to special chars. (#1444) [Kanad Kanhere]

****  Fix performance when mulithreaded on 1 CPU. (#1455) [Stefan Wallentowitz]

****  Fix type and real parameter issues (#1427) (#1456) (#1458) [Todd Strader]

****  Fix build error on MinGW. (#1460) [Richard Myers]

****  Fix not reporting some duplicate signals. (#1462) [Peter Gerst]

****  Fix --savable invalid C++ on packed arrays. (#1465) [Alex Chadwick]

****  Fix constant function return of function var. (#1467) [Roman Popov]


* Verilator 4.014 2019-05-08

***   Add --trace-fst-thread.

****  Support '#' comments in $readmem. (#1411) [Frederick Requin]

****  Support "'dx" constants. (#1423) [Udi Finkelstein]

****  For FST tracing use LZ4 compression. [Tony Bybell]

****  Add error when use parameters without value. (#1424) [Peter Gerst]

****  Auto-extend and WIDTH warn on unsized X/Zs. (#1423) [Udi Finkelstein]

****  Fix missing VL_SHIFTL_ errors. (#1412) (#1415) [Larry Lee]

****  Fix MinGW GCC 6 printf formats. (#1413) [Sergey Kvachonok]

****  Fix test problems when missing fst2vcd. (#1417) [Todd Strader]

****  Fix GTKWave register warning. (#1421) [Pieter Kapsenberg]

****  Fix FST enums not displaying. (#1426) [Danilo Ramos]

****  Fix table compile error with multiinterfaces. (#1431) [Bogdan Vukobratovic]


* Verilator 4.012 2019-03-23

***   Add +verilator+seed. (#1396) [Stan Sokorac]

***   Support $fread. [Leendert van Doorn]

***   Support void' cast on functions called as tasks. (#1383) [Al Grant]

***   Add IGNOREDRETURN warning. (#1383)

****  Report PORTSHORT errors on concat constants. (#1400) [Will Korteland]

****  Fix VERILATOR_GDB being ignored. (#2017) [Yu Sheng Lin]

****  Fix $value$plus$args missing verilated_heavy.h. [Yi-Chung Chen]

****  Fix MSVC compile error. (#1406) [Benjamin Gartner]

****  Fix maintainer test when no Parallel::Forker. (#1977) [Enzo Chi]

****  Fix +1364-1995ext flags applying too late. (#1384) [Al Grant]


* Verilator 4.010 2019-01-27

***   Removed --trace-lxt2, use --trace-fst instead.

****  For --xml, add additional information. (#1372) [Jonathan Kimmitt]

****  Add circular typedef error. (#1388)  [Al Grant]

****  Add unsupported for loops error. (#1986) [Yu Sheng Lin]

****  Fix FST tracing of wide arrays. (#1376) [Aleksander Osman]

****  Fix error when pattern assignment has too few elements. (#1378) [Viktor Tomov]

****  Fix error when no modules in $unit. (#1381) [Al Grant]

****  Fix missing too many digits warning. (#1380) [Jonathan Kimmitt]

****  Fix uninitialized data in verFiles and unroller. (#1385) (#1386) [Al Grant]

****  Fix internal error on xrefs into unrolled functions. (#1387) [Al Grant]

****  Fix DPI export void compiler error. (#1391) [Stan Sokorac]


* Verilator 4.008 2018-12-01

***   Support "ref" and "const ref" pins and functions. (#1360) [Jake Longo]

***   In --xml-only show the original unmodified names, and add module_files
      and cells similar to Verilog-Perl, msg2719. [Kanad Kanhere]

****  Add CONTASSREG error on continuous assignments to regs. (#1369) [Peter Gerst]

****  Add PROCASSWIRE error on behavioral assignments to wires, msg2737. [Neil Turton]

****  Add IMPORTSTAR warning on import::* inside $unit scope.

****  Fix --trace-lxt2 compile error on MinGW. (#1990) [HyungKi Jeong]

****  Fix hang on bad pattern keys. (#1364) [Matt Myers]

****  Fix crash due to cygwin bug in getline. (#1349) [Affe Mao]

****  Fix __Slow files getting compiled with OPT_FAST. (#1370) [Thomas Watts]


* Verilator 4.006 2018-10-27

**    Add --pp-comments. (#1988) [Robert Henry]

**    Add --dump-defines.

***   For --trace-fst, save enum decoding information. (#1358) [Sergi Granell]
      (To visualize enumeration data you must use GTKwave 3.3.95 or newer.)

***   For --trace-fst, instead of *.fst.hier, put data into *.fst. [Tony Bybell]

****  Fix --trace-lxt2 compile error on MinGW, msg2667. [HyungKi Jeong]

****  Fix Windows .exe not found. (#1361) [Patrick Stewart]


* Verilator 4.004 2018-10-06

**    Add GTKWave FST native tracing. (#1356) [Sergi Granell]
      (Verilator developers need to pull the latest vcddiff.)

***   Support $past. [Dan Gisselquist]

***   Support restrict. (#1350) [Clifford Wolf]

***   Rename include/lxt2 to include/gtkwave.

****  Fix replication of 64-bit signal change detects.

****  Fix Mac OSX 10.13.6 / LLVM 9.1 compile issues. (#1348) [Kevin Kiningham]

****  Fix MinGW compile issues. (#1979) [HyungKi Jeong]


* Verilator 4.002 2018-09-16

**    This is a major release. Any patches may require major rework to apply.
      [Thanks everyone]

**    Add multithreaded model generation.

**    Add runtime arguments.

**    Add GTKWave LXT2 native tracing. (#1333) [Yu Sheng Lin]

**    Note $random has new algorithm; results may vary vs. previous versions.

***   Better optimize large always block splitting. (#1244) [John Coiner]

***   Add new reloop optimization for repetitive assignment compression.

***   Support string.atoi and similar methods. (#1289) [Joel Holdsworth]

****  Fix internals to be C++ null-pointer-check clean.

****  Fix internals to avoid 'using namespace std'.

****  Fix Verilation performance issues. (#1316) [John Coiner]

****  Fix clocker attributes to not propagate on concats. [John Coiner]

****  Fix first clock edge and --x-initial-edge. (#1327) [Rupert Swarbrick]

****  Fix compile error on tracing of string arrays. (#1338) [Iztok Jeras]

****  Fix number parsing with newline after radix. (#1340) [George Cuan]

****  Fix string ?: conditional type resolution. (#1345) [Iztok Jeras]

****  Fix duplicate symbol error on generate tri. (#1347) [Tomas Dzetkulic]


* Verilator 3.926 2018-08-22

****  Add OBJCACHE envvar support to examples and generated Makefiles.

****  Change MODDUP errors to warnings. (#1969) [Marshal Qiao]

****  Fix define argument stringification (`"), broke since 3.914. [Joe DErrico]

****  Fix to ignore Unicode UTF-8 BOM sequences. (#1967) [HyungKi Jeong]

****  Fix std:: build error. (#1322)

****  Fix function inlining inside certain while loops. (#1330) [Julien Margetts]


* Verilator 3.924 2018-06-12

***   Renamed --profile-cfuncs to --prof-cfuncs.

****  Report interface ports connected to wrong interface. (#1294) [Todd Strader]

****  When tracing, use scalars on single bit arrays to appease vcddiff.

****  Fix parsing "output signed" in V2K port list, msg2540. [James Jung]

****  Fix parsing error on bad missing #. (#1308) [Dan Kirkham]

****  Fix $clog2 to be in verilog 2005. (#1319) [James Hutchinson]


* Verilator 3.922 2018-03-17

**    Support IEEE 1800-2017 as default language.

***   Support trig functions ($sin() etc). (#1281) [Patrick Stewart]

***   Support calling system functions as tasks. (#1285) [Joel Holdsworth]

***   Support assert properties. (#785) (#1290) [John Coiner, et al]

***   Support $writememh. [John Coiner]

***   Add --no-debug-leak to reduce memory use under debug. [John Coiner]

****  Fix severe runtime performance bug in certain foreach loops. [John Coiner]

****  On convergence errors, show activity. [John Coiner]

****  Fix GCC 8.0 issues. (#1273)

****  Fix pullup/pulldowns on bit selects. (#1274) [Rob Stoddard]

****  Fix verilator_coverage --annotate-min. (#1284) [Tymoteusz Blazejczyk]

****  Fix quoting of quoted arguments. [John Coiner]


* Verilator 3.920 2018-02-01

**    Moving forward, use the git "stable" branch to track the latest release,
      and git "v#.###" tags for specific releases.

***   Support 'assume' similar to 'assert'. (#1269) [Dan Gisselquist]

****  Fix tracing example file output. (#1268) [Enzo Chi]

****  Fix gate optimization out of memory, add --gate-stmts. (#1260) [Alex Solomatnikov]

****  Fix compile error on public real parameters by suppressing. (#1261) [Alex Solomatnikov]

****  Fix input-only tristate comparisons. (#1267) [Alexis G]

****  Fix missing edge type in xml output. (#1955) [Alexis G]

****  Fix compile error with --public and interface bind. (#1264) [Alexis G]

****  Remove c++filt. (#1265) [Stefan Wallentowitz]


* Verilator 3.918 2018-01-02

***   Workaround GCC/clang bug with huge compile times. (#1248)

***   Support DPI open arrays. (#909) (#1245) [David Pierce, Victor Besyakov]

***   Add INFINITELOOP warning. (#1254) [Alex Solomatnikov]

****  Support > 64 bit decimal $display.

****  Support DPI time and svLogicVal. [Victor Besyakov]
      Note older version incorrectly assumed svBitVal even for logicals.

****  Support string len() method. [Victor Besyakov]

****  Add error if always_comb has sensitivity list. [Arjen Roodselaar]

****  Fix SystemC 2.3.2 compile error. (#1251) [Tymoteusz Blazejczyk]

****  Fix modport outputs being treated as inputs. (#1246) [Jeff Bush]

****  Fix false ALWCOMBORDER on interface references. (#1247) [Josh Redford]

****  Fix constant propagation across DPI imports of inout strings. [Victor Besyakov]

****  Fix resolving inline nested interface names. (#1250) [Arjen Roodselaar]

****  Fix GCC false warning on array bounds. (#2386)


* Verilator 3.916 2017-11-25

***   Support self-recursive modules. (#659) [Sean Moore, et al]

***   Support $error/$warning in elaboration time blocks.

***   Support $size/$bits/etc on type references.

***   Add error when driving input-only modport. (#1110) [Trevor Elbourne]

***   Add BSSPACE and COLONPLUS lint warnings.

****  Detect MSB overflow when under VL_DEBUG. (#1238) [Junyi Xi]

****  Add data types to --xml. [Rui Terra]

****  Fix partial slicing with pattern assignments. (#991) [Johan Bjork]

****  Fix false unused warning on interfaces. (#1241) [Laurens van Dam]

****  Fix error on "unique case" with no cases.

****  Fix MacOS portability. (#1232) [Jeff Bush]


* Verilator 3.914 2017-10-14

**    Added new examples/ directory with appropriate examples. This replaces the
      old test_c and test_sc directories.

***   Add --getenv option for simplifying Makefiles.

***   Add --x-initial option for specifying initial value assignment behavior.

***   Add --no-relative-cfuncs and related default optimization. (#1224) [John Coiner]

***   Add /*verilator tag*/ for XML extraction applications. [Chris Randall]

****  The internal test_verilated test directory is moved to be part of test_regress.

****  The experimental VL_THREADED setting (only, not normal mode) now requires C++11.

****  Fix over-aggressive inlining. (#1223) [John Coiner]

****  Fix Ubuntu 17.10 issues. (#1223 partial). [John Coiner]

****  Fix compiler warning when WIDTH warning ignored on large compare.

****  Fix memory leak in VerilatedVcd dumps. (#1222 partial) [Shareef Jalloq]

****  Fix unnecessary Vdly variables. (#1224 partial) [John Coiner]

****  Fix conditional slices and add related optimizations.

****  Fix `` expansion of `defines. (#1225) (#1227) (#1228) [Odd Magne Reitan]

****  Fix -E duplicating output. (#1226) [Odd Magne Reitan]

****  Fix float-conversion warning. (#1229) [Robert Henry]

****  Fix MacOS portability. (#1230) (#1231) [Jeff Bush]


* Verilator 3.912 2017-09-23

**    Verilated headers no longer "use namespace std;"
      User's code without "std::" prefixes may need "use namespace std;" to compile.

***   Support or/and/xor array intrinsic methods. (#1210) [Mike Popoloski]

***   Support package export. (#1217) [Usuario Eda]

***   Fix ordering of arrayed cell wide connections. (#1202 partial) [Mike Popoloski]

****  Support module port parameters without defaults. (#1213) [Mike Popoloski]

****  Add performance information to --stats file.

****  Simplify VL_CONST_W macro generation for faster compiles.

****  Fix LITENDIAN warning on arrayed cells. (#1202) [Mike Popoloski]

****  Fix enum ranges without colons. (#1204) [Mike Popoloski]

****  Fix GCC noreturn compile error. (#1209) [Mike Popoloski]

****  Fix constant function default parameters. (#1211) [Mike Popoloski]

****  Fix non-colon array of interface modports. (#1212) [Mike Popoloski]

****  Fix .name connections on interfaces. (#1214) [Mike Popoloski]

****  Fix wide array indices causing compile error.

****  Better optimize Shift-And, and replication constructs.


* Verilator 3.910 2017-09-07

***   SystemPerl mode (-sp-deprecated) has been removed.

****  Update keyword warnings to include C++11 and others.


* Verilator 3.908 2017-08-28

****  Support x in $readmem. (#1180) [Arthur Kahlich]

****  Support packed struct DPI imports. (#1190) [Rob Stoddard]

****  Fix GCC 6 warnings.

****  Fix compile error on unused VL_VALUEPLUSARGS_IW. (#1181) [Thomas J Whatson]

****  Fix undefined VL_POW_WWI. [Clifford Wolf]

****  Fix internal error on unconnected inouts. (#1187) [Rob Stoddard]


* Verilator 3.906 2017-06-22

***   Support set_time_unit/set_time_precision in C traces. (#1937)

***   Fix extract of packed array with non-zero LSB. (#1172) [James Pallister]

***   Fix shifts by more than 32-bit numbers. (#1174) [Clifford Wolf]

***   Fix power operator on wide constants. (#761) [Clifford Wolf]

***   Fix .* on interface pins. (#1176) [Maciej Piechotka]


* Verilator 3.904 2017-05-30

***   Fix non-cutable ordering loops on clock arrays. (#1009) [Todd Strader]

***   Support ports of array of reals. (#1154) [J Briquet]

***   Support arrayed parameter overrides. (#1153) [John Stevenson]

***   Support $value$plusargs with variables. (#1165) [Wesley Terpstra]

****  Support modport access to un-modport objects. (#1161) [Todd Strader]

****  Add stack trace when can't optimize function. (#1158) [Todd Strader]

****  Add warning on mis-sized literal. (#1156) [Todd Strader]

****  Fix interface functions returning wrong parameters. (#996) [Todd Strader]

****  Fix non-arrayed cells with interface arrays. (#1153) [John Stevenson]

****  Fix --assert with complex case statements. (#1164) [Enzo Chi]


* Verilator 3.902 2017-04-02

**    Add -FI option to force includes. (#1916) [Amir Gonnen]

**    Add --relative-includes. [Rob Stoddard]

***   Add error on duplicate pattern assignments. (#1145) [Johan Bjork]

****  Fix error on improperly widthed default function. (#984) [Todd Strader]

****  Fix 2009 localparam syntax, msg2139. [Galen Seitz]

****  Fix ugly interface-to-non-interface errors. (#1112) [Johan Bjork]

****  Fix LDFLAGS and CFLAGS not preserving order. (#1130) [Olof Kindgren]

****  Fix internal error on initializing parameter array. (#1131) [Jie Xu]

****  Fix internal error on interface arrays. (#1135) [John Stevenson]

****  Fix calling sformatf to display, and elab $displays. (#1139) [Johan Bjork]

****  Fix realpath compile issue on MSVC++. (#1141) [Miodrag Milanovic]

****  Fix missing error on interface size mismatch. (#1143)  [Johan Bjork]

****  Fix error on parameters with dotted references. (#1146) [Johan Bjork]

****  Fix wreal not handling continuous assign. (#1150) [J Briquet]

****  Fix nested structure parameter selects. (#1150) [J Briquet]


* Verilator 3.900 2017-01-15

**    Internal code changes for improved compatibility and performance.

***   Support old-style $display($time). (#467) [John Demme]

****  With --bbox-unsup, suppress desassign and mixed edges. (#1120) [Galen Seitz]

****  Fix parsing sensitivity with &&. (#934) [Luke Yang]

****  Fix internal error on double-for loop unrolling. (#1044) [Jan Egil Ruud]

****  Fix internal error on unique casez with --assert. (#1117) [Enzo Chi]

****  Fix bad code when tracing array of structs. (#1122) [Andrew Bardsley]


* Verilator 3.890 2016-11-25

***   Honor --output-split on coverage constructors. (#1098) [Johan Bjork]

****  Fix various issues when making outside of the kit.

****  Fix flex 2.6.2 bug. (#1103) [Sergey Kvachonok]

****  Fix error on bad interface name. (#1097) [Todd Strader]

****  Fix error on referencing variable in parent. (#1099) [Ian Thompson]

****  Fix type parameters with low optimization. (#1101) [Stefan Wallentowitz]


* Verilator 3.888 2016-10-14

**    Support foreach. (#1078) [Xuan Guo]

***   Add --no-decoration to remove output comments, msg2015. [Frederic Requin]

***   If VM_PARALLEL_BUILDS=1, use OPT_FAST and OPT_SLOW. [Frederic Requin]
      Set VM_DEFAULT_RULES=0 for old behavior.

****  Add error on DPI functions > 32 bits. (#1898) [Elliot Mednick]

****  Fix SystemC compiles with VPI. (#1081) [Arthur Kahlich]

****  Fix error on wide numbers that represent shifts, msg1991. (#1088) [Mandy Xu]

****  Improve Verilation performance on internal strings. (#1896) [Johan Bjork]

****  Improve Verilation performance on trace duplicates. (#1090) [Johan Bjork]


* Verilator 3.886 2016-07-30

****  Fix enum values of 11-16 bits wide using .next/.prev. (#1062) [Brian Flachs]

****  Fix false warnings on non-power-2 enums using .next/.prev.

****  Fix comparison of unpacked arrays. (#1071) [Andrew Bardsley]

****  Fix compiler warning in GCC 6. [David Horton]


* Verilator 3.884 2016-05-18

**    Support parameter type. (#376) [Alan Hunter, et al]

**    Support command-line -G/+pvalue param overrides. (#1045) [Stefan Wallentowitz]

***   The default l2 scope name is now the same as the top-level module. (#1050)
      Use "--l2-name v" for the historical behavior.

***   Add --l2-name option for controlling "v" naming.

****  Fix --output-split of constructors. (#1035) [Johan Bjork]

****  Fix removal of empty packages, modules and cells. (#1034) [Johan Bjork]

****  Fix core dump on Arch Linux/GCC 6.1.1. (#1058) [Jannis Harder]

****  Fix $value$plusargs to string. (#1880) [Frederic Requin]


* Verilator 3.882 2016-03-01

****  Internal Verilation-time performance enhancements. (#1021) [Johan Bjork]

****  Support inlining interfaces. (#1018) [Johan Bjork]

****  Support SV strings to readmemh. (#1040) [Stefan Wallentowitz]

****  Fix unrolling complicated for-loop bounds. (#677) [Johan Bjork]

****  Fix stats file containing multiple unroll entries. (#1020) [Johan Bjork]

****  Fix using short parameter names on negative params. (#1022) [Duraid Madina]

****  Fix read-after-free error. (#1031) [Johan Bjork]

****  Fix elaboration-time display warnings. (#1032) [Johan Bjork]

****  Fix crash on very deep function trees. (#1028) [Jonathan Kimmitt]

****  Fix slicing mix of big and little-endian. (#1033) [Geoff Barrett]

****  Fix pattern assignment width propagation. (#1037) [Johan Bjork]


* Verilator 3.880 2015-12-19

***   Support display %u, %v, %p, %z. (#989) [Johan Bjork]

****  Fix real parameters causing bad module names. (#992) [Johan Bjork]

****  Fix size-changing cast on packed struct. (#993) [Johan Bjork]

****  Fix function calls on arrayed interface. (#994) [Johan Bjork]

****  Fix arrayed interfaces. (#879) (#1001) [Todd Strader]

****  Fix constant function assigned to packed structs. (#997) [Johan Bjork]

****  Fix interface inside generate. (#998) [Johan Bjork]

****  Fix $signed casts under generates. (#999) [Clifford Wolf]

****  Fix genvar constant propagation. (#1003) [Johan Bjork]

****  Fix parameter constant propagation from package. (#1004) [Johan Bjork]

****  Fix array slicing of non-const indexes. (#1006) [Johan Bjork]

****  Fix dotted generated array error. (#1005) [Jeff Bush, Johan Bjork]

****  Fix error instead of warning on large concat. (#1865) [Paul Rolfe]

****  Fix $bitstoreal constant propagation. (#1012) [Jonathan Kimmitt]

****  Fix model restore crash. (#1013) [Jason McMullan]

****  Fix arrayed instances to unpacked of same size. (#1015) [Varun Koyyalagunta]

****  Fix slices of unpacked arrays with non-zero LSBs.

****  Fix ternary operation with unpacked array. (#1017) [Varun Koyyalagunta].


* Verilator 3.878 2015-11-01

**    Add --vpi flag, and fix VPI linkage. (#969) [Arthur Kahlich]

**    Support genvar indexes into arrayed cells. (#517)  [Todd Strader]

**    Support $sformatf. (#977) [Johan Bjork]

***   Support elaboration assertions. (#973) [Johan Bjork]

***   Support $display with non-format arguments. (#467) [Jamey Hicks]

****  Add VerilatedScopeNameMap for introspection. (#966) [Todd Strader]

****  Ignore %l in $display. (#983) [Todd Strader]

****  Fix very long module names. (#937) [Todd Strader]

****  Fix internal error on dotted refs into generates. (#958) [Jie Xu]

****  Fix structure parameter constant propagation. (#968) [Todd Strader]

****  Fix enum constant propagation. (#970) [Todd Strader]

****  Fix mis-optimizing public DPI functions. (#963) [Wei Song]

****  Fix package:scope.scope variable references.

****  Fix $fwrite to constant stderr/stdout. (#961) [Wei Song]

****  Fix struct.enum.name method calls. (#855) [Jonathon Donaldson]

****  Fix dot indexing into arrayed inferfaces. (#978)  [Johan Bjork]

****  Fix crash in commandArgsPlusMatch. (#987) [Jamie Iles]

****  Fix error message on missing interface. (#985) [Todd Strader]


* Verilator 3.876 2015-08-12

***   Add tracing_on, etc to vlt files. (#932) [Frederic Requin]

****  Support extraction of enum bits. (#951) [Jonathon Donaldson]

****  Fix MinGW compiler error. (#927) (#929) [Hans Tichelaar]

****  Fix .c files to be treated as .cpp. (#930) [Jonathon Donaldson]

****  Fix string-to-int space conversion. (#931) [Fabrizio Ferrandi]

****  Fix dpi imports inside generates. [Michael Tresidder]

****  Fix rounding in trace $timescale. (#946) [Frederic Requin]

****  Fix $fopen with SV string. (#947) [Sven Stucki]

****  Fix hashed error with typedef inside block. (#948) [Sven Stucki]

****  Fix makefile with --coverage. (#953) [Eivind Liland]

****  Fix coverage documentation. (#954) [Thomas J Whatson]

****  Fix parameters with function parameter arguments. (#952) [Jie Xu]

****  Fix size casts as second argument of cast item. (#950) [Jonathon Donaldson]


* Verilator 3.874 2015-06-06

***   Add pkg-config .pc file. (#919) [Stefan Wallentowitz]

****  Fix installing missing manpages. (#908) [Ahmed El-Mahmoudy]

****  Fix sign extension in large localparams. (#910) [Mike Thyer]

****  Fix core dump in sync-async warnings. (#911) [Sebastian Dressler]

****  Fix truncation warning with -pins-bv. (#912) [Alfonso Martinez]

****  Fix Cygwin uint32 compile. (#914) [Matthew Barr]

****  Fix preprocessing stringified newline escapes. (#915) [Anton Rapp]

****  Fix part-select in constant function. (#916) [Andrew Bardsley]

****  Fix width extension on mis-width ports. (#918) [Patrick Maupin]

****  Fix width propagation on sized casts. (#925) [Jonathon Donaldson]

****  Fix MSVC++ compiler error. (#927) [Hans Tichelaar]


* Verilator 3.872 2015-04-05

***   Add VerilatedVcdFile to allow real-time waveforms. (#890) [HyungKi Jeong]

***   Add --clk and related optimizations. (#1840) [Jie Xu]

***   Fix order of C style arrays. [Duraid Madina]

****  Add --dump-treei-<srcfile>. (#894) [Jie Xu]

****  Fix comma-instantiations with parameters. (#884) [Franck Jullien]

****  Fix SystemC arrayed bit vectors. (#886) [David Poole]

****  Fix compile error on MinGW. (#887) [HyungKi Jeong]


* Verilator 3.870 2015-02-12

****  Suppress COMBDLY when inside always_latch. (#864) [Iztok Jeras]

****  Support cast operator with expression size. (#865) [Iztok Jeras]

****  Add warning on slice selection out of bounds. (#875) [Cong Van Nguyen].

****  Fix member select error broke in 3.868. (#867) [Iztok Jeras]

****  Fix $sccanf from string. (#866) [David Pierce]

****  Fix VM_PARALLEL_BUILDS broke in 3.868. (#870) [Hiroki Honda]

****  Fix non-ANSI modport instantiations. (#868) [Kevin Thompson]

****  Fix UNOPTFLAT change detect on multidim arrays. (#872) [Andrew Bardsley]

****  Fix slice connections of arrays to ports. (#880) [Varun Koyyalagunta]

****  Fix mis-optimizing gate assignments in unopt blocks. (#881) [Mike Thyer]

****  Fix sign extension of pattern members. (#882) [Iztok Jeras]

****  Fix clang compile warnings.


* Verilator 3.868 2014-12-20

**    New verilator_coverage program added to replace SystemPerl's vcoverage.

**    PSL support was removed, please use System Verilog assertions.

**    SystemPerl mode is deprecated and now untested.

***   Support enum.first/name and similar methods. (#460) (#848)

***   Add 'string' printing and comparisons. (#746) (#747) etc.

***   Inline C functions that are used only once. (#1838) [Jie Xu]

***   Fix tracing SystemC signals with structures. (#858) [Eivind Liland]
      Note that SystemC traces will no longer show the signals
      in the wrapper, they can be seen one level further down.

****  Add --stats-vars. (#851) [Jeremy Bennett]

****  Fix bare generates in interfaces. (#789) [Bob Newgard]

****  Fix underscores in real literals. (#863) [Jonathon Donaldson]


* Verilator 3.866 2014-11-15

***   Fix +define+A+B to define A and B to match other simulators. (#847) [Adam Krolnik]

***   Add optimization of wires from arrayed cells. (#1831) [Jie Xu]

***   Add optimization of operators between concats. (#1831) [Jie Xu]

***   Add public enums. (#833) [Jonathon Donaldson]

***   Trace_off now operates on cells. (#826) [Lane Brooks]

****  Fix public parameters in unused packages. (#804) [Jonathon Donaldson]

****  Fix select when partially out-of-bound. (#823) [Cliffort Wolf]

****  Fix generate unrolling with function call. (#830) [Steven Slatter]

****  Fix cast-to-size context-determined sizing. (#828) [Geoff Barrett]

****  Fix not tracing modules following primitives. (#837) [Jie Xu]

****  Fix trace overflow on huge arrays. (#834) [Geoff Barrett]

****  Fix quoted comment slashes in defines. (#845) [Adam Krolnik]


* Verilator 3.864 2014-09-21

***   Support power operator with real. (#809) [Jonathon Donaldson]

****  Improve verilator_profcfunc time attributions. [Jonathon Donaldson]

****  Fix duplicate anonymous structures in $root. (#788) [Bob Newgard]

****  Fix mis-optimization of bit-swap in wide signal. (#800) [Jie Xu]

****  Fix error when tracing public parameters. (#722) [Jonathon Donaldson]

****  Fix dpiGetContext in dotted scopes. (#740) [Geoff Barrett]

****  Fix over-shift structure optimization error. (#803) [Jeff Bush]

****  Fix optional parameter keyword in module #(). (#810) [Iztok Jeras]

****  Fix $warning/$error multi-argument ordering. (#816) [Jonathon Donaldson]

****  Fix clang warnings. (#818) [Iztok Jeras]

****  Fix string formats under deep expressions. (#820) [Iztok Jeras]


* Verilator 3.862 2014-06-10

***   Using command line -Wno-{WARNING} now overrides file-local lint_on.

***   Add -P to suppress `line and blanks with preprocessing. (#781) [Derek Lockhart]

***   Support SV 2012 package import before port list.

****  Change SYMRSVDWORD to print as warning rather than error.

****  Fix seg-fault with variable of parameterized interface. (#692) [Jie Xu]

****  Fix false name conflict on cells in generate blocks. (#749) [Igor Lesik]

****  Fix pattern assignment to basic types. (#767) [Jie Xu]

****  Fix pattern assignment to conditionals. (#769) [Jie Xu]

****  Fix shift corner-cases. (#765) (#766) (#768) (#772) (#774) (#776) [Clifford Wolf]

****  Fix C compiler interpreting signing. (#773) [Clifford Wolf]

****  Fix late constant division by zero giving X error. (#775) [Clifford Wolf]

****  Fix gate primitives with arrays and non-arrayed pins.

****  Fix DETECTARRAY error on packed arrays. (#770) [Jie Xu]

****  Fix ENDLABEL warnings on escaped identifiers.

****  Fix string corruption. (#780) [Derek Lockhart]


* Verilator 3.860 2014-05-11

**    PSL is no longer supported, please use System Verilog assertions.

**    Support '{} assignment pattern on arrays. (#355)

**    Support streaming operators. (#649) [Glen Gibb]

**    Fix expression problems with -Wno-WIDTH. (#729) (#736) (#737) (#759)
      Where WIDTH warnings were ignored this might result in different
      warning messages and results, though it should better match the spec.
      [Clifford Wolf]

***   Add --no-trace-params.

***   Add assertions on 'unique if'. (#725) [Jeff Bush]

***   Add PINCONNECTEMPTY warning. [Holger Waechtler]

***   Support parameter arrays. (#683) [Jeremy Bennett]

***   Fix begin_keywords "1800+VAMS". (#1806)

****  Documentation fixes. (#723) [Glen Gibb]

****  Support {} in always sensitivity lists. (#745) [Igor Lesik]

****  Fix tracing of package variables and real arrays.

****  Fix tracing of packed arrays without --trace-structs. (#742) [Jie Xu]

****  Fix missing coverage line on else-if. (#727) [Sharad Bagri]

****  Fix modport function import not-found error.

****  Fix power operator calculation. (#730) (#735) [Clifford Wolf]

****  Fix reporting struct members as reserved words. (#741) [Chris Randall]

****  Fix change detection error on unions. (#758) [Jie Xu]

****  Fix -Wno-UNOPTFLAT change detection with 64-bits. (#762) [Clifford Wolf]

****  Fix shift-right optimization. (#763) [Clifford Wolf]

****  Fix Mac OS-X test issues. [Holger Waechtler]

****  Fix C++-2011 warnings.


* Verilator 3.856 2014-03-11

***   Support case inside. (#708) [Jan Egil Ruud]

***   Add parameters into trace files. (#706) [Alex Solomatnikov]

****  Fix parsing "#0 'b0". (#256)

****  Fix array bound checks on real variables.

****  Fix --skip-identical mis-detecting on OS-X. (#707)

****  Fix missing VL_SHIFTRS_IQI with WIDTH warning. (#714) [Fabrizio Ferrandi]

****  Fix signed shift right optimization. (#715) [Fabrizio Ferrandi]

****  Fix internal error on "input x =" syntax error. (#716) [Lane Brooks]

****  Fix slice extraction from packed array. (#717) [Jan Egil Ruud]

****  Fix inside statement EQWILD error. (#718) [Jan Egil Ruud]


* Verilator 3.855 2014-01-18

***   Support modport import. (#696) [Jeremy Bennett]

***   Add --trace-structs to show struct names. (#673) [Chris Randall]

****  Fix tracing of packed structs. (#705) [Jie Xu]

****  Fix --lint-only with MinGW. (#1813) [HyungKi Jeong]

****  Fix some delayed assignments of typedefed unpacked arrays.

****  Fix wire declarations with size and not range. (#466) [Alex Solomatnikov]

****  Fix parameter pin vs. normal pin error. (#704) [Alex Solomatnikov]


* Verilator 3.854 2013-11-26

***   Add UNPACKED warning to convert unpacked structs. [Jeremy Bennett]

***   Add --compiler clang to work around compiler bug. (#694) [Stefan Ludwig]

****  Support vpi_get of vpiSuppressVal. (#687) [Varun Koyyalagunta]

****  Support vpi_get_time. (#688) [Varun Koyyalagunta]

****  Fix evaluation of chained parameter functions. (#684) [Ted Campbell]

****  Fix enum value extension of '1.

****  Fix multiple VPI variable callbacks. (#679) [Rich Porter]

****  Fix vpi_get of vpiSize. (#680) [Rich Porter]

****  Fix vpi_remove_cb inside callback. (#689) [Varun Koyyalagunta]

****  Fix crash with coverage of structures. (#691) [Eivind Liland]

****  Fix array assignment from const var. (#693) [Jie Xu]


* Verilator 3.853 2013-09-30

****  Add --no-order-clock-delay to work around #613. [Charlie Brej]


* Verilator 3.852 2013-09-29

***   Support named function and task arguments. [Chris Randall]

***   Report SELRANGE warning for non-generate if. (#675) [Roland Kruse]

****  Fix ordering of $fgetc. (#1808) [Frederic Requin]

****  Fix --output-split-cfunc to count internal functions. [Chris Randall]

****  Fix crash on 32-bit Ubuntu. (#670) [Mark Jackson Pulver]


* Verilator 3.851 2013-08-15

***   Fix ordering of clock enables with delayed assigns. (#613) [Jeremy Bennett]

***   Fix vpi_iterate on memory words. (#655) [Rich Porter]

****  Fix final duplicate declarations when non-inlined. (#661) [Charlie Brej]

****  Fix interface ports with comma lists. (#1779) [Ed Lander]

****  Fix parameter real conversion from integer.

****  Fix clang warnings. (#668)  [Yutetsu Takatsukasa]


* Verilator 3.850 2013-06-02

**    Support interfaces and modports. (#102)  [Byron Bradley, Jeremy Bennett]

***   Duplicate clock gate optimization on by default. (#621)

****  Fix arrayed input compile error. (#645) [Krzysztof Jankowski]

****  Fix GCC version runtime changes. (#651) [Jeremy Bennett]

****  Fix packed array select internal error. (#652) [Krzysztof Jankowski]


* Verilator 3.847 2013-05-11

***   Add ALWCOMBORDER warning. [KC Buckenmaier]

***   Add --pins-sc-uint and --pins-sc-biguint. (#638) [Alex Hornung]

****  Support "signal[vec]++".

****  Fix simulation error when inputs and MULTIDRIVEN. (#634) [Ted Campbell]

****  Fix module resolution with __. (#631) [Jason McMullan]

****  Fix packed array non-zero right index select crash. (#642) [Krzysztof Jankowski]

****  Fix nested union crash. (#643) [Krzysztof Jankowski]


* Verilator 3.846 2013-03-09

**    IEEE 1800-2012 is now the default language. This adds 4 new keywords
      and updates the svdpi.h and vpi_user.h header files.

***   Add --report-unoptflat. (#611) [Jeremy Bennett]

***   Add duplicate clock gate optimization. (#1772) [Varun Koyyalagunta]
      Disabled unless -OD or -O3 used, please try it as may get some
      significant speedups.

***   Fix wrong dot resolution under inlining. [Art Stamness]

****  Support pattern assignment features. (#616) (#617) (#618) [Ed Lander]

****  Support bind in $unit. (#602) [Ed Lander]

****  Support <number>'() sized casts. (#628) [Ed Lander]

****  Fix DETECTARRAY on packed structures. (#610) [Jeremy Bennett]

****  Fix LITENDIAN on unpacked structures. (#614) [Wai Sum Mong]

****  Fix 32-bit OS VPI scan issue. (#615)  [Jeremy Bennett, Rich Porter]

****  Fix opening a VerilatedVcdC file multiple times. (#1774) [Frederic Requin]

****  Fix UNOPTFLAT circular array bounds crossing. (#630) [Jie Xu]


* Verilator 3.845 2013-02-04

***   Fix nested packed arrays and struct. (#600) [Jeremy Bennett]
      Packed arrays are now represented as a single linear vector in
      Verilated models. This may affect packed arrays that are public or
      accessed via the VPI.

***   Support wires with data types. (#608) [Ed Lander]

***   Support bind, to module names only. (#602) [Ed Lander]

***   Support VPI product info, warning calls, etc. (#588) [Rick Porter]

***   Support $left, $right and related functions. (#448) [Iztok Jeras]

***   Support inside expressions.

***   Define SYSTEMVERILOG, SV_COV_START and other IEEE mandated predefines.

****  Fix pin width mismatch error. (#595)  [Alex Solomatnikov]

****  Fix implicit one bit parameter selection. (#603)  [Jeremy Bennett]

****  Fix signed/unsigned parameter misconversion. (#606)  [Jeremy Bennett]

****  Fix segfault on multidimensional dotted arrays. (#607)  [Jie Xu]

****  Fix per-bit array output connection error. (#414)  [Jan Egil Ruud]

****  Fix package logic var compile error.

****  Fix enums with X values.


* Verilator 3.844 2013-01-09

***   Support "unsigned int" DPI import functions. (#1770)  [Alex Lee]

***   Fix package resolution of parameters. (#586) [Jeremy Bennett]

****  Fix non-integer vpi_get_value. (#587)  [Rich Porter]

****  Fix task inlining under $display and case. (#589) (#598)  [Holger Waechtler]

****  Fix package import of non-localparam parameter. (#474) (#591)  [Jeremy Bennett]

****  Fix package import of package imports, partial #592. [Jeremy Bennett]

****  Fix package import preventing local var. (#599)  [Jeremy Bennett]

****  Fix array extraction of implicit vars. (#601)  [Joe Eiler]


* Verilator 3.843 2012-12-01

***   Add +1364-1995ext and similar language options. (#532)  [Jeremy Bennett]

****  Fix mis-optimized identical submodule subtract. (#581)  [Charlie Brej]

****  Fix crash on dotted references into dead modules. (#583)  [Jeremy Bennett]

****  Fix compile issues on MSVCC. (#571) (#577)  [Amir Gonnen]

****  Fix --debug overriding preceding --dump-treei. (#580)  [Jeremy Bennett]


* Verilator 3.842 2012-11-03

****  Add -x-initial-edge. (#570)  [Jeremy Bennett]

****  Fix parameter pins interspersed with cells broke in 3.840. [Bernard Deadman]

****  Fix large shift error on large shift constants. [David Welch]

****  Fix $display mangling on GCC 4.7 and speed up. (#1765) (#373) (#574) [R Diez]

****  Fix array of struct references giving false error. (#566) [Julius Baxter]

****  Fix missing var access functions when no DPI. (#572) [Amir Gonnen]

****  Fix name collision on unnamed blocks. (#567)  [Chandan Egbert]

****  Fix name collision on task inputs. (#569)  [Chandan Egbert]


* Verilator 3.841 2012-09-03

***   Add --savable to support model save/restore. [Jeremy Bennett]

***   Support '{} assignment pattern on structures, part of #355.

****  Fix double-deep parameter cell WIDTHs. (#541)  [Hiroki Honda]

****  Fix imports under multiple instantiated cells. (#542)  [Alex Solomatnikov]

****  Fix defparam in generate broke in 3.840. (#543)  [Alex Solomatnikov]

****  Fix duplicate begin error broke in 3.840. (#548)  [Alex Solomatnikov]

****  Fix triangle symbol resolution error broke in 3.840. (#550)  [Ted Campbell]


* Verilator 3.840 2012-07-31 Beta

**    Rewrote tristate handling; supports tri0, tri1, tristate bit selects,
      concatenates and pullup/pulldowns. (#395) (#56) (#54) (#51)
      [Alex Solomatnikov, Lane Brooks, et al]

**    Support packed structures and unions. (#181)
      Note this was a major internal change that may lead to some instability.

***   Support tri0 and tri1. (#462)  [Alex Solomatnikov]

***   Support nmos and pmos. (#488)  [Alex Solomatnikov]

***   Add INITIALDLY warning on initial assignments. (#478)  [Alex Solomatnikov]

***   Add PINMISSING and PINNOCONNECT lint checks.

***   Add --converge-limit option.

***   Fix generate operators not short circuiting. (#413)  [by Jeremy Bennett]

***   Fix parameters not supported in constant functions. (#474) [Alex Solomatnikov]

****  Fix duplicate warnings/errors. (#516)  [Alex Solomatnikov]

****  Fix signed extending biops with WIDTH warning off. (#511) [Junji Hashimoto]

****  Fix ITOD internal error on real conversions. (#491)  [Alex Solomatnikov]

****  Fix input and real loosing real data type. (#501)  [Alex Solomatnikov]

****  Fix imports causing symbol table error. (#490)  [Alex Solomatnikov]

****  Fix newlines in radix values. (#507) [Walter Lavino]

****  Fix loop error message to report line. (#513)  [Jeremy Bennett]

****  Fix false UNUSED warning on file system calls.

****  Fix GCC 4.7.0 compile warnings. (#530)  [Jeremy Bennett]

****  Fix svdpi.h compile error on Apple OS.

****  Fix compile error under git submodules. (#534) [Aurelien Francillon]


* Verilator 3.833 2012-04-15

***   Support += and -= in standard for loops. (#463) [Alex Solomatnikov]

***   Fix processing unused parametrized modules. (#469) (#470)  [Alex Solomatnikov]

****  Add SELRANGE as warning instead of error. (#477) [Alex Solomatnikov]

****  Add readme.pdf and internal.pdf and doxygen. (#483)  [by Jeremy Bennett]

****  Fix change detections on arrays. (#364)  [John Stevenson, Alex Solomatnikov]

****  Fix signed array warning. (#456) [Alex Solomatnikov]

****  Fix genvar and begin under generate. (#461)  [Alex Solomatnikov]

****  Fix real constant parameter functions. (#475)  [Alex Solomatnikov]

****  Fix and document --gdb option. (#454) [Jeremy Bennett]

****  Fix OpenSolaris compile error. [Sanjay Singh]


* Verilator 3.832 2012-03-07

***   Fix memory delayed assignments from multiple clock domains. [Andrew Ling]

***   Support arrayed SystemC I/O pins. [Christophe Joly]

***   Report MULTIDRIVEN on memories set in multiple clock domains.

***   Report ENDLABEL on mismatching end labels. (#450) [Iztok Jeras]

****  Fix expansion of back-slashed escaped macros. (#441) [Alberto Del Rio]

****  Fix inheriting real and signed type across untyped parameters.

****  Fix core dump with over 100 deep UNOPTFLAT. (#432) [Joe Eiler]

****  Fix false command not found warning in makefiles. [Ruben Diez]

****  Fix hang when functions inside begin block. [David Welch]

****  Fix hang on recursive substitution `defines. (#443) [Alex Solomatnikov]


* Verilator 3.831 2012-01-20

**    Support SystemC 2.3.0 prerelease. This requires setting the new
      SYSTEMC_INCLUDE and SYSTEMC_LIBDIR variables in place of now
      deprecated SYSTEMC and SYSTEMC_ARCH. [Iztok Jeras]

****  Suppress VARHIDDEN on dpi import arguments. [Ruben Diez]

****  Support "generate for (genvar i=0; ...". [David Kravitz]

****  Fix dpi exports with > 32 bit but < 64 bit args. (#423) [Chandan Egbert]

****  Fix array of instantiations with sub-range output. (#414) [Jeremy Bennett]

****  Fix BLKSEQ warnings on variables declared inside always. [Ruben Diez]


* Verilator 3.830 2011-11-27

**   With "--language VAMS" support a touch of Verilog AMS. [Holger Waechtler]

***  Add sc_bv attribute to force bit vectors. (#402) [by Stefan Wallentowitz]

**** Search for user -y paths before default current directory. [Ruben Diez]

**** Support constants in sensitivity lists. (#412)  [Jeremy Bennett]

**** Support $system. [Ruben Diez]

**** Support $sscanf with %g. [Holger Waechtler]

**** Indicate 'exiting due to errors' if errors, not warnings. [Ruben Diez]

**** Fix bad result with if-else-return optimization. (#420) [Alex Solomatnikov]

**** Fix reporting not found modules if generate-off. (#403) [Jeremy Bennett]

**** Fix $display with %d following %g. [Holger Waechtler]


* Verilator 3.824 2011-10-25

***  Fix "always @ (* )". (#403) (#404)  [Walter Lavino]

***  Add ASSIGNIN as suppressable error. [Jeremy Bennett]

**** Fix 3.823 constructor core dump on Debian. (#401)  [Ahmed El-Mahmoudy]


* Verilator 3.823 2011-10-20

***  Support $ceil, $floor, etc. [Alex Solomatnikov]

***  Add configure options for cc warnings and extended tests. [Ruben Diez]

***  Add -Wall reporting ASSIGNDLY on assignment delays. [Ruben Diez]

***  Fix UNDRIVEN warnings inside DPI import functions. [Ruben Diez]

***  Fix --help output to go to stderr, not stdout. (#397)  [Ruben Diez]

**** Fix DPI import output of 64 bits. (#398) [Mike Denio]

**** Fix DPI import false BLKSEQ warnings. [Alex Solomatnikov]

**** Fix MSVC compile warning with trunc/round. (#394) [Amir Gonnen]

**** Fix autoconf and Makefile warnings. (#396)  [Ruben Diez]


* Verilator 3.821 2011-09-14

**** Fix PowerPC runtime error. (#288) [Ahmed El-Mahmoudy]

**** Fix internal error on integer casts. (#374) [Chandan Egbert]


* Verilator 3.820 2011-07-28

**   Support 'real' numbers and related functions.

***  Support 'const' variables in limited cases; similar to enums. [Alex Solomatnikov]

***  Support disable for loop escapes.

***  Support $fopen and I/O with integer instead of `verilator_file_descriptor.

***  Support coverage in -cc and -sc output modes. [John Li]
     Note this requires SystemPerl 1.338 or newer.

**** Fix vpi_register_cb using bad s_cb_data. (#370)  [by Thomas Watts]

**** Fix $display missing leading zeros in %0d. (#367)  [Alex Solomatnikov]

**** Use 'vluint64_t' for SystemC instead of (same sized) 'uint64' for MSVC++.


* Verilator 3.813 2011-06-28

***  Support bit vectors > 64 bits wide in DPI import and exports.

***  Fix out of memory on slice syntax error. (#354)  [Alex Solomatnikov]

**** Fix error on enum references to other packages. (#339) [Alex Solomatnikov]

**** Fix DPI undeclared svBitVecVal compile error. (#346) [Chandan Egbert]

**** Fix DPI bit vector compile errors. (#347) (#359) [Chandan Egbert]

**** Fix CDCRSTLOGIC report showing endpoint flops without resets.

**** Fix compiler warnings on SPARC. (#288) [Ahmed El-Mahmoudy]


* Verilator 3.812 2011-04-06

***  Add --trace-max-width and --trace-max-array. (#319)  [Alex Solomatnikov]

***  Add --Wno-fatal to turn off abort on warnings. [by Stefan Wallentowitz]

**** Support ${...} and $(...) env vars in .vc files. [by Stefan Wallentowitz]

**** Support $bits(data_type). (#327)  [Alex Solomatnikov]

**** Support loop unrolling on width mismatches. (#333) [Joe Eiler]

**** Support simple cast operators. (#335)  [Alex Solomatnikov]

**** Accelerate bit-selected inversions.

**** Add error on circular parameter definitions. (#329) [Alex Solomatnikov]

**** Fix concatenates and vectored bufif1. (#326) [Iztok Jeras]


* Verilator 3.811 2011-02-14

**** Report errors on duplicated or empty pins. (#321)  [Christian Leber]

**** Report error on function call output tied to constant. [Bernard Deadman]

**** Throw UNUSED/UNDRIVEN only once per net in a parametrized module.

**** Fix internal error on functions called as SV tasks. [Bernard Deadman]

**** Fix internal error on non-inlined inout pins. [Jeff Winston]

**** Fix false BLKSEQ on non-unrolled for loop indexes. [Jeff Winston]

**** Fix block comment not separating identifiers. (#311) [Gene Sullivan]

**** Fix warnings to point to lowest net usage, not upper level ports.

**** Fix error on constants connected to outputs. (#323)  [Christian Leber]


* Verilator 3.810 2011-01-03

**   Add limited support for VPI access to public signals, see docs.

***  Add -F option to read relative option files. (#297) [Neil Hamilton]

***  Support ++,--,+= etc as standalone statements. [Alex Solomatnikov]

**** When running with VERILATOR_ROOT, optionally find binaries under bin.

**** Suppress WIDTH warnings when adding/subtracting 1'b1.

**   Add -Wall, -Wwarn-style, -Wno-style to enable code style warnings
     that have been added to this release, and disabled by default:

***  With --Wall, add BLKSEQ warning on blocking assignments in seq blocks.

***  With --Wall, add DECLFILENAME warning on modules not matching filename.

***  With --Wall, add DEFPARAM warning on deprecated defparam statements.

***  With --Wall, add IFDEPTH warning on deep if statements.

***  With --Wall, add INCABSPATH warning on `include with absolute paths.

***  With --Wall, add SYNCASYNCNET warning on mixed sync/async reset nets.

***  With --Wall, add UNDRIVEN warning on undriven nets.

***  With --Wall, add UNUSED warning on unused nets.

***  The VARHIDDEN warning is now disabled by default, use -Wall to enable.


* Verilator 3.805 2010-11-02

**** Add warning when directory contains spaces. (#1705)  [Salman Sheikh]

**** Fix wrong filename on include file errors. (#289) [Brad Parker]

**** Fix segfault on SystemVerilog "output wire foo=0". (#291)  [Joshua Wise]

**** Fix DPI export name not found. (#1703)  [Terry Chen]


* Verilator 3.804 2010-09-20

***  Support tracing/coverage of underscore signals. (#280)  [by Jason McMullan]

**** Fix preprocessor `` of existing base define. (#283)  [Usha Priyadharshini]

**** Increase define recursions before error. [Paul Liu]

**** On core dump, print debug suggestions.


* Verilator 3.803 2010-07-10

***  Fix preprocessor preservation of newlines across macro substitutions.

**** Fix preprocessor stringification of nested macros.

**** Fix some constant parameter functions causing crash. (#253) [Nick Bowler]

**** Fix do {...} while() not requiring final semicolon.


* Verilator 3.802 2010-05-01

***  Support runtime access to public signal names.

***  Add /*verilator public_flat_rw*/ for timing-specific public access.

***  Fix word size to match uint64_t on -m64 systems. (#238) [Joe Eiler]

**** Improve error handling on slices of arrays. (#226) [by Byron Bradley]

**** Report errors when extra underscores used in meta-comments.

**** Fix bit reductions on multi-packed dimensions. (#227) [by Byron Bradley]

**** Fix removing $fscanf if assigned to unused var. (#248) [Ashutosh Das]

**** Fix "make install" with configure outside srcdir. [Stefan Wallentowitz]

**** Fix loop unroller out of memory; change --unroll-stmts. [Ashutosh Das]

**** Fix trace files with empty modules crashing some viewers.

**** Fix parsing single files > 2GB. [Jeffrey Short]

**** Fix installing data files as non-executable. (#168) [by Ahmed El-Mahmoudy]


* Verilator 3.801 2010-03-17

***  Support "break", "continue", "return".

***  Support "`default_nettype none|wire". [Dominic Plunkett]

**** Skip SystemC tests if not installed. [Iztok Jeras]

**** Fix clock-gates with non-AND complex logic. (#220) [Ashutosh Das]

**** Fix flushing VCD buffers on $stop. [Ashutosh Das]

**** Fix Mac OS-X compile issues. (#217)  [Joshua Wise, Trevor Williams]

**** Fix make uninstall. (#216)  [Iztok Jeras]

**** Fix parametrized defines with empty arguments.


* Verilator 3.800 2010-02-07

Application visible changes:

**   SystemPerl is no longer required for tracing.
     Applications must use VerilatedVcdC class in place of SpTraceVcdC.

**   SystemVerilog 1800-2009 is now the default language.
     Thus "global" etc are now keywords. See the --language option.

New features:

**   Support SystemVerilog types "byte", "chandle", "int", "longint",
     "shortint", "time", "var" and "void" in variables and functions.

**   Support "program", "package", "import" and $unit.

**   Support typedef and enum. [by Donal Casey]

**   Support direct programming interface (DPI) "import" and "export".
     Includes an extension to map user $system PLI calls to the DPI.

***  Support assignments of multidimensional slices. (#170) [by Byron Bradley]

***  Support multidimensional inputs/outputs. (#171) [by Byron Bradley]

***  Support "reg [1:0][1:0][1:0]" and "reg x [3][2]". (#176)  [Byron Bradley]

***  Support declarations in loop initializers. (#172)  [by Byron Bradley]

***  Support $test$plusargs and $value$plusargs, but see the docs!

***  Support $sformat and $swrite.

***  Support 1800-2009 define defaults and `undefineall.

***  Add -CFLAGS, -LDFLAGS, <file>.a, <file>.o, and <file>.so options.

***  Speed compiles by avoiding including the STL iostream header.
     Application programs may need to include it themselves to avoid errors.

***  Add experimental clock domain crossing checks.

***  Add experimental --pipe-filter to filter all Verilog input.

***  Add experimental config files to filter warnings outside of the source.

***  Add VARHIDDEN warning when signal name hides module name.

**** Support optional cell parenthesis. (#179) [by Byron Bradley]

**** Support for loop i++, ++i, i--, --i. (#175) [by Byron Bradley]

**** Support 1800-2009 /*comments*/ in define values.

**** Add Makefile VM_GLOBAL_FAST, listing objects needed to link executables.

**** Add --bbox-unsup option to black-box unsupported UDP tables.

**** Add -Wno-MODDUP option to allow duplicate modules.

Bug fixes:

**** Fix implicit variable issues. (#196) (#201) [Byron Bradley]

**** Fix 'for' variable typing. (#205)  [by Byron Bradley]

**** Fix tracing with --pins-bv 1. (#195)  [Michael S]

**** Fix MSVC++ 2008 compile issues. (#209)  [Amir Gonnen]

**** Fix MinGW compilation. (#184) (#214) [by Shankar Giri, Amir Gonnen]

**** Fix Cygwin 1.7.x compiler error with uint32_t. (#204)  [Ivan Djordjevic]

**** Fix `define argument mis-replacing system task of same name. (#191)

**** Fix Verilator core dump on wide integer divides. (#178) [Byron Bradley]

**** Fix lint_off/lint_on meta comments on same line as warning.


* Verilator 3.720 2009-10-26

**   Support little endian bit vectors ("reg [0:2] x;").

**   Support division and modulus of > 64 bit vectors. [Gary Thomas]

***  Fix writing to out-of-bounds arrays writing element 0.

**** Fix core dump with SystemVerilog var declarations under unnamed begins.

**** Fix VCD files showing internal flattened hierarchy, broke in 3.714.

**** Fix cell port connection to unsized integer causing false width warning.

**** Fix erroring on strings with backslashed newlines. (#168) [Pete Nixon]


* Verilator 3.714 2009-09-18

**   Add --bbox-sys option to blackbox $system calls.

**   Support generate for var++, var--, ++var, --var.

***  Improved warning when "do" used as identifier.

**** Don't require SYSTEMPERL_INCLUDE if SYSTEMPERL/src exists. [Gary Thomas]

**** Fix deep defines causing flex scanner overflows. [Brad Dobbie]

**** Fix preprocessing commas in deep parameterized macros. [Brad Dobbie]

**** Fix tracing escaped dotted identifiers. (#107)

**** Fix $display with uppercase %M.

**** Fix --error-limit option being ignored.


* Verilator 3.713 2009-08-04

**   Support constant function calls for parameters. [many!]

***  Support SystemVerilog "logic". (#101)  [by Alex Duller]

***  Name SYMRSVDWORD error, and allow disabling it. (#103) [Gary Thomas]

**** Fix escaped preprocessor identifiers. (#106) [Nimrod Gileadi]


* Verilator 3.712 2009-07-14

**   Patching SystemC is no longer required to trace sc_bvs.

***  Support zero-width constants in concatenations. [Jeff Winston]

***  Add verilator --pins-uint8 option to use sc_in<uint8_t/uint16_t>.

***  Add verilator -V option, to show verbose version.

***  On WIDTH warnings, show variable name causing error. [Jeff Winston]

**** Add BLKLOOPINIT error code, and describe --unroll-count. [Jeff Winston]


* Verilator 3.711 2009-06-23

**** Support decimal constants of arbitrary widths. [Mark Marshall]

**** Fix error on case statement with all duplicate items. (#99) [Gary Thomas]

**** Fix segfault on unrolling for's with bad inits. (#90) [Andreas Olofsson]

**** Fix tristates causing "Assigned pin is neither...". [by Lane Brooks]

**** Fix compiler errors under Fedora release candidate 11. [Chitlesh Goorah]


* Verilator 3.710 2009-05-19

**   Verilator is now licensed under LGPL v3 and/or Artistic v2.0.

***  `__FILE__ now expands to a string, per draft SystemVerilog 2010(ish).

**** The front end parser has been re-factored to enable more SV parsing.
     Code should parse the same, but minor parsing bugs may pop up.

**** Verilator_includer is no longer installed twice. (#48)  [Lane Brooks]

**** Fix escaped identifiers with '.' causing conflicts. (#83)  [J Baxter]

**** Fix define formal arguments that contain newlines. (#84) [David A]


* Verilator 3.703 2009-05-02

***  Fix $clog2 calculation error with powers-of-2. (#81) [Patricio Kaplan]

**** Fix error with tasks that have output first. (#78)  [Andrea Foletto]

**** Fix "cloning" error with -y/--top-module. (#76) [Dimitris Nalbantis]

**** Fix segfault with error on bad --top-module. (#79) [Dimitris Nalbantis]

**** Fix "redefining I" error with complex includes. [Duraid Madina]

**** Fix GCC 4.3.2 compile warnings.


* Verilator 3.702 2009-03-28

***  Add --pins-bv option to use sc_bv for all ports. [Brian Small]

***  Add SYSTEMPERL_INCLUDE envvar to assist RPM builds. [Chitlesh Goorah]

**** Report errors when duplicate labels are used. (#72)  [Vasu Kandadi]

**** Fix the SC_MODULE name() to not include __PVT__. [Bob Fredieu]


* Verilator 3.701 2009-02-26

**   Support repeat and forever statements. [Jeremy Bennett]

***  Add --debugi-<srcfile> option, for internal debugging. [Dennis Muhlestein]

**** Fix compile issues with GCC 4.3. (#47)  [Lane Brooks]

**** Fix VL_RANDom to better randomize bits. [Art Stamness]

**** Fix error messages to consistently go to stderr. [Jeremy Bennett]

**** Fix left associativity for ?: operators.


* Verilator 3.700 2009-01-08

**   Add limited support for tristate inouts. Written by Lane Brooks,
     under support by Ubixum Inc. This allows common pad ring and
     tristate-mux structures to be Verilated. See the documentation for
     more information on supported constructs.

**   Add --coverage_toggle for toggle coverage analysis.
     Running coverage now requires SystemPerl 1.301 or newer.

***  Add /*verilator coverage_on/_off */ to bracket coverage regions.

***  Optimize two-level shift and and/or trees, +23% on one test.

***  Support posedge of bit-selected signals. (#45) [Rodney Sinclair]

***  Line coverage now aggregates by hierarchy automatically.
     Previously this would be done inside SystemPerl, which was slower.

**** Minor performance improvements of Verilator compiler runtime.

**** Coverage of each parametarized module is counted separately. [Bob Fredieu]

**** Fix creating parameterized modules when no parameter values are changed.

**** Fix certain generate-if cells causing "clone" error. [Stephane Laurent]

**** Fix line coverage of public functions. [Soon Koh]

**** Fix SystemC 2.2 deprecated warnings about sensitive() and sc_start().

**** Fix arrayed variables under function not compiling. (#44) [Ralf Karge]

**** Fix --output-split-cfuncs to also split trace code. [Niranjan Prabhu]

**** Fix 'bad select range' warning missing some cases. (#43) [Lane Brooks]

**** Fix internal signal names containing control characters (broke in 3.680).

**** Fix compile error on Ubuntu 8.10. [Christopher Boumenot]

**** Fix internal error on "output x; reg x = y;".

**** Fix wrong result for read of delayed FSM signal. (#46) [Rodney Sinclair]


* Verilator 3.681 2008-11-12

***  Add SystemVerilog unique and priority case.

**** Include Verilog file's directory name in coverage reports.

**** Fix 'for' under 'generate-for' causing error. (#38) [Rafael Shirakawa]

**** Fix coverage hierarchy being backwards with inlining. [Vasu Arasanipalai]

**** Fix GCC 4.3 compile error. (#35)  [Lane Brooks]

**** Fix MSVC compile error. (#42)  [John Stroebel]


* Verilator 3.680 2008-10-08

**   Support negative bit indexes. [Stephane Laurent]
     Tracing negative indexes requires latest Verilog-Perl and SystemPerl.

***  Suppress width warnings between constant strings and wider vectors.
     [Rodney Sinclair]

**** Ignore SystemVerilog timeunit and timeprecision.

**** Expand environment variables in -f input files. [Lawrence Butcher]

**** Report error if port declaration is missing. (#32) [Guy-Armand Kamendje]

**** Fix genvars causing link error when using --public. [Chris Candler]


* Verilator 3.671 2008-09-19

**   SystemC uint64_t pins are now the default instead of sc_bv<64>.
     Use --no-pins64 for backward compatibility.

***  Support SystemVerilog "cover property" statements.

***  When warnings are disabled on signals that are flattened out, disable
     the warnings on the signal(s) that replace it.

***  Add by-design and by-module subtotals to verilator_profcfunc.

***  Fix extra evaluation of pure combo blocks in SystemC output.

**** Add IMPERFECTSCH warning, disabled by default.

**** Support coverage under SystemPerl 1.285 and newer.

**** Fix stack overflow on large ? : trees. [John Sanguinetti]

**** Support arbitrary characters in identifiers. [Stephane Laurent]


* Verilator 3.670 2008-07-23

**   Add --x-assign=fast option, and make it the default.
     This chooses performance over reset debugging. See the manual.

**   Add --autoflush, for flushing streams after $display. [Steve Tong]

**   Add CASEWITHX lint warning and if disabled fix handling of casez with Xs.

***  Add $feof, $fgetc, $fgets, $fflush, $fscanf, $sscanf. [Holger Waechtler]

***  Add $stime. [Holger Waechtler]

***  Add $random.

***  Add --Wfuture-, for improving forward compatibility.

**** Fix verilator_includer not being installed properly. [Holger Waechtler]

**** Fix IMPURE errors due to X-assignment temporary variables. [Steve Tong]

**** Fix "lvalue" errors with public functions. (#25)  [CY Wang]

**** Add WIDTH warning to $fopen etc file descriptors.

**** Internal changes to how $displays get compiled and executed.


* Verilator 3.665 2008-06-25

**** Ignore "// verilator" comments alone on endif lines. [Rodney Sinclair]

**** "Make install" now installs verilator_includer and verilator_profcfunc.

**** Fix tracing missing changes on undriven public wires. [Rodney Sinclair]

**** Fix syntax error when "`include `defname" is ifdefed. [John Dickol]

**** Fix error when macro call has commas in concatenate. [John Dickol]

**** Fix compile errors under Fedora 9, GCC 4.3.0. [by Jeremy Bennett]

**** Fix Makefile to find headers/libraries under prefix. [by Holger Waechtler]


* Verilator 3.664 2008-05-08

**** Fix missing file in kit.


* Verilator 3.663 2008-05-07

**** Add DESTDIR to Makefiles to assist RPM construction. [Gunter Dannoritzer]

**** Fix compiler warnings under GCC 4.2.1.

**** Fix preprocessor `else after series of `elsif. [Mark Nodine]

**** Fix parametrized defines calling define with comma. [Joshua Wise]

**** Fix comma separated list of primitives. [by Bryan Brady]


* Verilator 3.662 2008-04-25

***  Add Verilog 2005 $clog2() function.
     This is useful in calculating bus-widths from parameters.

***  Support /**/ comments in -f option files. [Stefan Thiede]

**** Add error message when modules have duplicate names. [Stefan Thiede]

**** Support defines terminated in EOF, though against spec. [Stefan Thiede]

**** Support optional argument to $finish and $stop. [by Stefan Thiede]

**** Support ranges on gate primitive instantiations. [Stefan Thiede]

**** Ignore old standard(ish) Verilog-XL defines. [by Stefan Thiede]

**** Fix "always @ ((a) or (b))" syntax error. [by Niranjan Prabhu]

**** Fix "output reg name=expr;" syntax error. [Martin Scharrer]

**** Fix multiple .v files being read in random order. [Stefan Thiede]

**** Fix internal error when params get non-constants. [Johan Wouters]

**** Fix bug introduced in 3.661 with parametrized defines.


* Verilator 3.661 2008-04-04

***  The --enable-defenv configure option added in 3.660 is now the default.
     This hard-codes a default for VERILATOR_ROOT etc in the executables.

***  Add --language option for supporting older code. [Stefan Thiede]

***  Add --top-module option to select between multiple tops. [Stefan Thiede]

***  Unsized concatenates now give WIDTHCONCAT warnings. [Jonathan Kimmitt]
     Previously they threw fatal errors, which in most cases is correct
     according to spec, but can be incorrect in presence of parameter values.

**** Support functions with "input integer". [Johan Wouters]

**** Ignore delays attached to gate UDPs. [Stefan Thiede]

**** Fix SystemVerilog parameterized defines with `` expansion,
     and fix extra whitespace inserted on substitution. [Vladimir Matveyenko]

**** Fix no-module include files on command line. [Stefan Thiede]

**** Fix dropping of backslash quoted-quote at end of $display.

**** Fix task output pin connected to non-variables. [Jonathan Kimmitt]

**** Fix missing test_v in install datadir. [Holger Waechtler]

**** Fix internal error after MSB < LSB error reported to user. [Stefan Thiede]


* Verilator 3.660 2008-03-23

***  Add support for hard-coding VERILATOR_ROOT etc in the executables,
     to enable easier use of Verilator RPMs. [Gunter Dannoritzer]

***  Allow multiple .v files on command line. [Stefan Thiede]

***  Convert re-defining macro error to warning. [Stefan Thiede]

***  Add --error-limit option. [Stefan Thiede]

***  Allow __ in cell names by quoting them in C. [Stefan Thiede]

**** Fix genvar to be signed, so "< 0" works properly. [Niranjan Prabhu]

**** Fix assignments to inputs inside functions/tasks. [Patricio Kaplan]

**** Fix definitions in main file.v, referenced in library. [Stefan Thiede]

**** Fix undefined assigns to be implicit warnings. [Stefan Thiede]


* Verilator 3.658 2008-02-25

**** Fix unistd compile error in 3.657. [Patricio Kaplan, Jonathan Kimmitt]


* Verilator 3.657 2008-02-20

**** Fix assignments of {a,b,c} = {c,b,a}. [Jonathan Kimmitt]

**** Fix Perl warning with --lint-only. [by Ding Xiaoliang]

**** Avoid creating obj_dir with --lint-only. [Ding Xiaoliang]

**** Fix parsing of always @(*). [Patricio Kaplan]


* Verilator 3.656 2008-01-18

**** Wide VL_CONST_W_#X functions are now made automatically. [Bernard Deadman]
     In such cases, a new {prefix}__Inlines.h file will be built and included.

**** Fixed sign error when extracting from signed memory. [Peter Debacker]

**** Fixed tracing of SystemC w/o SystemPerl. [Bernard Deadman, Johan Wouters]


* Verilator 3.655 2007-11-27

***  Support "#delay <statement>;" with associated STMTDLY warning.

**** Fixed generate for loops with constant zero conditions. [Rodney Sinclair]

**** Fixed divide-by-zero errors in constant propagator. [Rodney Sinclair]

**** Fixed wrong result with obscure signed-shift underneath a "? :".

**** Fixed many internal memory leaks, and added leak detector.


* Verilator 3.654 2007-10-18

**** Don't exit early if many warnings but no errors are found. [Stan Mayer]

**** Fixed parsing module #(parameter x,y) declarations. [Oleg Rodionov]

**** Fixed parsing system functions with empty parens. [Oleg Rodionov]


* Verilator 3.653 2007-08-01

**** Support SystemVerilog ==? and !=? operators.

**** Fixed SC_LIBS missing from generated makefiles. [Ding Xiaoliang]


* Verilator 3.652 2007-06-21

**** Report as many warning types as possible before exiting.

**** Support V2K portlists with "input a,b,...". [Mark Nodine]

**** Support V2K function/task argument lists.

**** Optimize constant $display arguments.

**** Fixed Preprocessor dropping some `line directives. [Mark Nodine]


* Verilator 3.651 2007-05-22

***  Added verilator_profcfunc utility. [Gene Weber]

***  Treat modules within `celldefine and `endcelldefine as if in library.

***  Support functions which return integers. [Mark Nodine]

**** Warn if flex is not installed. [Ralf Karge]

**** Ignore `protect and `endprotect.

**** Allow empty case/endcase blocks.


* Verilator 3.650 2007-04-20

**   Add --compiler msvc option. This is now required when Verilated code
     is to be run through MSVC++. This also enables fixing MSVC++ error
     C1061, blocks nested too deeply. [Ralf Karge]

**   Add --lint-only option, to lint without creating other output.

***  Add /*verilator lint_save*/ and /*verilator lint_restore*/ to allow
     friendly control over re-enabling lint messages. [Gerald Williams]

***  Support SystemVerilog .name and .* interconnect.

***  Support while and do-while loops.

***  Use $(LINK) instead of $(CXX) for Makefile link rules. [Gerald Williams]

***  Add USER_CPPFLAGS and USER_LDFLAGS to Makefiles. [Gerald Williams]

**** Fixed compile errors under Windows MINGW compiler. [Gerald Williams]

**** Fixed dotted bit reference to local memory. [Eugene Weber]

**** Fixed 3.640 `verilog forcing IEEE 1364-1995 only. [David Hewson]


* Verilator 3.640 2007-03-12

***  Support Verilog 2005 `begin_keywords and `end_keywords.

***  Updated list of SystemVerilog keywords to correspond to IEEE 1800-2005.

***  Add /*verilator public_flat*/. [Eugene Weber]

**** Try all +libext's in the exact order given. [Michael Shinkarovsky]

**** Fixed elimination of public signals assigned to constants. [Eugene Weber]

**** Fixed internal error when public for loop has empty body. [David Addison]

**** Fixed "Loops detected" assertion when model exceeds 4GB. [David Hewson]

**** Fixed display %m names inside named blocks.


* Verilator 3.633 2007-02-07

***  Add --trace-depth option for minimizing VCD file size. [Emerson Suguimoto]

***  With VL_DEBUG, show wires causing convergence errors. [Mike Shinkarovsky]

**** Fixed isolate_assignments when many signals per always. [Mike Shinkarovsky]

**** Fixed isolate_assignments across task/func temporaries. [Mike Shinkarovsky]

**** Fixed $display's with array select followed by wide AND. [David Hewson]


* Verilator 3.632 2007-01-17

***  Add /*verilator isolate_assignments*/ attribute. [Mike Shinkarovsky]


* Verilator 3.631 2007-01-02

**   Support standard NAME[#] for cells created by arraying or generate for.
     This replaces the non-standard name__# syntax used in earlier versions.

**** Fixed again dotted references into generate cells. [David Hewson]
     Verilator no longer accepts duplicated variables inside unique
     generate blocks as this is illegal according to the specification.

**** Fixed $readmem* with filenames < 8 characters. [Emerson Suguimoto]


* Verilator 3.630 2006-12-19

**   Support $readmemb and $readmemh. [Eugene Weber, Arthur Kahlich]

***  Fixed configure and compiling under Solaris. [Bob Farrell]

***  When dotted signal lookup fails, help the user by showing known scopes.

***  Reduce depth of priority encoded case statements. [Eugene Weber]

**** Fixed dotted references inside generated cells. [David Hewson]

**** Fixed missed split optimization points underneath other re-split blocks.


* Verilator 3.623 2006-12-05

***  Add --output-split-cfuncs for accelerating GCC compile. [Eugene Weber]

**** Fixed $signed mis-extending when input has a WIDTH violation. [Eugene Weber]

**** Add M32 make variable to support -m32 compiles. [Eugene Weber]


* Verilator 3.622 2006-10-17 Stable

**** Fixed --skip-identical without --debug, broken in 3.621. [Andy Meier]


* Verilator 3.621 2006-10-11 Beta

**   Add /*verilator no_inline_task*/ to prevent over-expansion. [Eugene Weber]

***  Public functions now allow > 64 bit arguments.

**** Remove .vpp intermediate files when not under --debug.

**** Fixed link error when using --exe with --trace. [Eugene Weber]

**** Fixed mis-optimization of wide concats with constants.

**** Fixed core dump on printing error when not under --debug. [Allan Cochrane]


* Verilator 3.620 2006-10-04 Stable

***  Support simple inout task ports. [Eugene Weber]

***  Allow overriding Perl, Flex and Bison versions. [by Robert Farrell]

***  Optimize variables set to constants within basic blocks for ~3%.

**** Default make no longer makes the docs; if you edit the documentation.
     sources, run "make info" to get them.

**** Optimize additional boolean identities (a|a = a, etc.)

**** Fixed coredump when dotted cross-ref inside task call. [Eugene Weber]

**** Fixed dotted variables in always sensitivity lists. [Allan Cochrane]


* Verilator 3.610 2006-09-20 Stable

***  Verilator now works under DJGPP (Pentium GCC). [John Stroebel]

**** Add default define for VL_PRINTF. [John Stroebel]

**** Removed coverage request variable; see Coverage limitations in docs.

**** Fixed DOS carriage returns in multiline defines. [Ralf Karge]

**** Fixed printf format warnings on 64-bit linux.


* Verilator 3.602 2006-09-11 Stable

**** Fixed function references under top inlined module. [David Hewson]


* Verilator 3.601 2006-09-06 Beta

***  Added --inhibit-sim flag for environments using old __Vm_inhibitSim.

***  Added `systemc_dtor for destructor extensions. [Allan Cochrane]

***  Added -MP to make phony dependencies, ala GCC's.

***  Changed how internal functions are invoked to reduce aliasing.
     Useful when using GCC's -O2 or -fstrict-aliasing, to gain another ~4%.

**** Fixed memory leak when destroying modules. [John Stroebel]

**** Fixed coredump when unused modules have unused cells. [David Hewson]

**** Fixed 3.600 internal error with arrayed instances. [David Hewson]

**** Fixed 3.600 internal error with non-unrolled function loops. [David Hewson]

**** Fixed $display %m name not matching Verilog name inside SystemC modules.

**** Declare optimized lookup tables as 'static', to reduce D-Cache miss rate.


* Verilator 3.600 2006-08-28 Beta

**   Support dotted cross-hierarchy variable and task references.

**** Lint for x's in generate case statements.

**** Fixed line numbers being off by one when first file starts with newline.

**** Fixed naming of generate for blocks to prevent non-inline name conflict.

**** Fixed redundant statements remaining after table optimization.


* Verilator 3.542 2006-08-11 Stable

**** Fixed extraneous UNSIGNED warning when comparing genvars. [David Hewson]

**** Fixed extra white space in $display %c. [by David Addison]

**** vl_finish and vl_fatal now print via VL_PRINTF rather then cerr/cout.

**** Add VL_CONST_W_24X macro. [Bernard Deadman]


* Verilator 3.541 2006-07-05 Beta

***  Fixed "// verilator lint_on" not re-enabling warnings. [David Hewson]

***  Fixed 3.540's multiple memory assignments to same block. [David Hewson]

**** Add warning on changeDetect to arrayed structures. [David Hewson]

**** Fixed non-zero start number for arrayed instantiations. [Jae Hossell]

**** Fixed GCC 4.0 header file warnings.


* Verilator 3.540 2006-06-27 Beta

**** Optimize combo assignments that are used only once, ~5-25% faster.

**** Optimize delayed assignments to memories inside loops, ~0-5% faster.

**** Fixed mis-width warning on bit selects of memories. [David Hewson]

**** Fixed mis-width warning on dead generate-if branches. [Jae Hossell]


* Verilator 3.533 2006-06-05 Stable

***  Add PDF user manual, verilator.pdf.

**** Fixed delayed bit-selected arrayed assignments. [David Hewson]

**** Fixed execution path to Perl. [Shanshan Xu]

**** Fixed Bison compile errors in verilog.y. [by Ben Jackson]


* Verilator 3.531 2006-05-10 Stable

***  Support $c routines which return 64 bit values.

**** Fixed `include `DEFINE.

**** Fixed Verilator core dump when have empty public function. [David.Hewson]


* Verilator 3.530 2006-04-24 Stable

**   $time is now 64 bits. The macro VL_TIME_I is now VL_TIME_Q, but calls
     the same sc_time_stamp() function to get the current time.


* Verilator 3.523 2006-03-06 Stable

**** Fixed error line numbers being off due to multi-line defines. [Mat Zeno]

**** Fixed GCC sign extending (uint64_t)(a<b). [David Hewson]

**** Fixed `systemc_imp_header "undefined macro" error.


* Verilator 3.522 2006-02-23 Beta

**** Add UNUSED error message, for forward compatibility.


* Verilator 3.521 2006-02-14 Beta

***  Create new --coverage-line and --coverage-user options. [Peter Holmes]

**** Added SystemVerilog 'x,'z,'0,'1, and new string literals.

**** Fixed public module's parent still getting inlined.


* Verilator 3.520 2006-01-14 Stable

**   Added support for $fopen, $fclose, $fwrite, $fdisplay.
     See documentation, as the file descriptors differ from the standard.


* Verilator 3.510 2005-12-17 Stable

**   Improve trace-on performance on large multi-clock designs by 2x or more.
     This adds a small ~2% performance penalty if traces are compiled in,
     but not turned on. For best non-tracing performance, do not use --trace.

**** Fixed $'s in specify delays causing bad PLI errors. [Mat Zeno]

**** Fixed public functions not setting up proper symbol table. [Mat Zeno]

**** Fixed genvars generating trace compile errors. [Mat Zeno]

**** Fixed VL_MULS_WWW compile error with MSVC++. [Wim Michiels]


* Verilator 3.502 2005-11-30 Stable

**** Fixed local non-IO variables in public functions and tasks.

**** Fixed bad lifetime optimization when same signal is assigned multiple
     times in both branch of a if. [Danny Ding]


* Verilator 3.501 2005-11-16 Stable

***  Add --prof-cfuncs for correlating profiles back to Verilog.

**** Fixed functions where regs are declared before inputs. [Danny Ding]

**** Fixed bad deep expressions with bit-selects and rotate. [Prabhat Gupta]


* Verilator 3.500 2005-10-30 Stable

**   Support signed numbers, >>>, $signed, $unsigned. [MANY!]

**   Support multi-dimensional arrays. [Eugen Fekete]

**   Add very limited support for the Property Specification Language
     (aka PSL or Sugar). The format and keywords are now very limited, but will
     grow with future releases. The --assert switch enables this feature.

**   With --assert, generate assertions for synthesis parallel_case and full_case.

**** Fixed generate if's with empty if/else blocks. [Mat Zeno]

**** Fixed generate for cell instantiations with same name. [Mat Zeno]


* Verilator 3.481 2005-10-12 Stable

***  Add /*verilator tracing_on/off*/ for waveform control.

**** Fixed split optimization reordering $display statements.


* Verilator 3.480 2005-09-27 Beta

**   Allow coverage of flattened modules, and multiple points per line.
     Coverage analysis requires SystemPerl 1.230 or newer.

**** Add preprocessor changes to support meta-comments.

**** Optimize sequential assignments of different bits of same bus; ~5% faster.

**** Optimize away duplicate lookup tables.

**** Optimize wide concatenates into individual words. [Ralf Karge]

**** Optimize local variables from delayed array assignments.


* Verilator 3.470 2005-09-06 Stable

***  Optimize staging flops under reset blocks.

***  Add '-Werror-...' to upgrade specific warnings to errors.

**** Add GCC branch prediction hints on generated if statements.

**** Fixed bad simulation when same function called twice in same expression.

**** Fixed preprocessor substitution of quoted parameterized defines.


* Verilator 3.464 2005-08-24 Stable

***  Add `systemc_imp_header, for use when using --output-split.

***  Add --stats option to dump design statistics.

**** Fixed core dump with clock inversion optimizations.


* Verilator 3.463 2005-08-05 Stable

***  Fixed case defaults when not last statement in case list. [Wim Michiels]


* Verilator 3.462 2005-08-03 Stable

***  Fixed reordering of delayed assignments to same memory index. [Wim Michiels]

**** Fixed compile error with Flex 2.5.1. [Jens Arm]

**** Fixed multiply-instantiated public tasks generating non-compilable code.


* Verilator 3.461 2005-07-28 Beta

**** Fixed compile error with older versions of bison. [Jeff Dutton]


* Verilator 3.460 2005-07-27 Beta

**   Add -output-split option to enable faster parallel GCC compiles.
     To support --output-split, the makefiles now split VM_CLASSES
     into VM_CLASSES_FAST and VM_CLASSES_SLOW. This may require a
     change to local makefiles.

**   Support -v argument to read library files.

***  When issuing unoptimizable warning, show an example path.

**** Fixed false warning when a clock is constant.

**** Fixed X/Z in decimal numbers. [Wim Michiels]

**** Fixed genvar statements in non-named generate blocks.

**** Fixed core dump when missing newline in `define. [David van der bokke]

**** Internal tree dumps now indicate edit number that changed the node.


* Verilator 3.450 2005-07-12

**   $finish will no longer exit, but set Verilated::gotFinish().
     This enables support for final statements, and for other cleanup code.
     If this is undesired, redefine the vl_user_finish routine. Top level
     loops should use Verilated::gotFinish() as a exit condition for their
     loop, and then call top->final(). To prevent a infinite loop, a
     double $finish will still exit; this may be removed in future
     releases.

***  Add support for SystemVerilog keywords $bits, $countones, $isunknown,
     $onehot, $onehot0, always_comb, always_ff, always_latch, finish.

**** Fixed "=== 1'bx" to always be false, instead of random.


* Verilator 3.440 2005-06-28 Stable

**   Add Verilog 2001 generate for/if/case statements.


* Verilator 3.431 2005-06-24 Stable

***  Fixed selection bugs introduced in 3.430 beta.


* Verilator 3.430 2005-06-22 Beta

**   Add Verilog 2001 variable part selects [n+:m] and [n-:m]. [Wim Michiels]


* Verilator 3.422 2005-06-10 Stable

***  Added Verilog 2001 power (**) operator. [Danny Ding]

**** Fixed crash and added error message when assigning to inputs. [Ralf Karge]

**** Fixed tracing of modules with public functions.


* Verilator 3.421 2005-06-02 Beta

**** Fixed error about reserved word on non-public signals.

**** Fixed missing initialization compile errors in 3.420 beta. [Ralf Karge]


* Verilator 3.420 2005-06-02 Beta

***  Fixed case defaults when not last statement in case list. [Ralf Karge]

**** Added error message when multiple defaults in case statement.

**** Fixed crash when wire self-assigns x=x.

**   Performance improvements worth ~20%

**   Added -x-assign options; ~5% faster if use -x-assign=0.

**** Optimize shifts out of conditionals and if statements.

**** Optimize local 'short' wires.

**** Fixed gate optimization with top-flattened modules. [Mahesh Kumashikar]


* Verilator 3.411 2005-05-30 Stable

**** Fixed compile error in GCC 2.96. [Jeff Dutton]


* Verilator 3.410 2005-05-25 Beta

**   Allow functions and tasks to be declared public.
     They will become public C++ functions, with appropriate C++ types.
     This allows users to make public accessor functions/tasks, instead
     of having to use public variables and `systemc_header hacks.

***  Skip producing output files if all inputs are identical
     This uses timestamps, similar to make. Disable with --no-skip-identical.

**** Improved compile performance with large case statements.

**** Fixed internal error in V3Table. [Jeff Dutton]

**** Fixed compile error in GCC 2.96, and with SystemC 1.2. [Jeff Dutton]


* Verilator 3.400 2005-04-29 Beta

**   Internal changes to support future clocking features.

**   Verilog-Perl and SystemPerl are no longer required for C++ or SystemC
     output. If you want tracing or coverage analysis, they are still needed.

***  Added --sc to create pure SystemC output not requiring SystemPerl.

***  Added --pins64 to create 64 bit SystemC outputs instead of sc_bv<64>.

***  The --exe flag is now required to produce executables inside the makefile.
     This was previously the case any time .cpp files were passed on the
     command line.

***  Added -O3 and --inline-mult for performance tuning. [Ralf Karge]
     One experiment regained 5% performance, at a cost of 300% in compile time.

***  Improved performance of large case/always statements with low fanin
     by converting to internal lookup tables (ROMs).

***  Initialize SystemC port names. [S Shuba]

**** Added Doxygen comments to Verilated includes.

**** Fixed -cc pins 8 bits wide and less to be uint8_t instead of uint16_t.

**** Fixed crash when Mdir has same name as .v file. [Gernot Koch]

**** Fixed crash with size mismatches on case items. [Gernot Koch]


* Verilator 3.340 2005-02-18 Stable

***  Report misconnected pins across all modules, instead of just first error.

**** Fixed over-active inlining, resulting in compile slowness.

**** Improved large netlist compile times.

**** Added additional internal assertions.


* Verilator 3.332 2005-01-27

***  Added -E preprocess only flag, similar to GCC.

***  Added CMPCONSTLR when comparison is constant due to > or < with all ones.

**** Fixed loss of first -f file argument, introduced in 3.331.


* Verilator 3.331 2005-01-18

**   The Verilog::Perl preprocessor is now C++ code inside of Verilator.
     This improves performance, makes compilation easier, and enables
     some future features.

***  Support arrays of instantiations (non-primitives only). [Wim Michiels]

**** Fixed unlinked error with defparam. [Shawn Wang]


* Verilator 3.320 2004-12-10

**   NEWS is now renamed Changes, to support CPAN indexing.

***  If Verilator is passed a C file, create a makefile link rule.
     This saves several user steps when compiling small projects.

***  Added new COMBDLY warning in place of fatal error. [Shawn Wang]

***  Fixed mis-simulation with wide-arrays under bit selects. [Ralf Karge]

**** Added NC Verilog as alternative to VCS for reference tests.

**** Support implicit wire declarations on input-only signals.
     (Dangerous, as leads to wires without drivers, but allowed by spec.)

**** Fixed compile warnings on Suse 9.1


* Verilator 3.311 2004-11-29

**   Support implicit wire declarations (as a warning). [Shawn Wang]

**** Fixed over-shift difference in Verilog vs C++. [Ralf Karge]


* Verilator 3.310 2004-11-15

**   Support defparam.

**   Support gate primitives: buf, not, and, nand, or, nor, xor, xnor.

***  Ignore all specify blocks.


* Verilator 3.302 2004-11-12

***  Support NAND and NOR operators.

***  Better warnings when port widths don't match.

**** Fixed internal error due to some port width mismatches. [Ralf Karge]

**** Fixed WIDTH warnings on modules that are only used
     parameterized, not in 'default' state.

**** Fixed selection of SystemC library on cygwin systems. [Shawn Wang]

**** Fixed runtime bit-selection of parameter constants.


* Verilator 3.301 2004-11-04

**** Fixed 64 bit [31:0] = {#{}} mis-simulation. [Ralf Karge]

**** Fixed shifts greater then word width mis-simulation. [Ralf Karge]

**** Work around GCC 2.96 negation bug.


* Verilator 3.300 2004-10-21

**   New backend that eliminates most VL_ macros.
     Improves performance 20%-50%, depending on frequency of use of signals
     over 64 bits. GCC compile times with -O2 shrink by a factor of 10.

**** Fixed "setting unsigned int from signed value" warning.


* Verilator 3.271 2004-10-21

**** Fixed "loops detected" error with some negedge clocks.

**** Cleaned up some output code spacing issues.


* Verilator 3.270 2004-10-15

***  Support Verilog 2001 parameters in module headers. [Ralf Karge]

**** Suppress numeric fault when dividing by zero.

**** Faster code to support compilers not inlining all Verilated functions.


* Verilator 3.260 2004-10-07

**   Support Verilog 2001 named parameter instantiation. [Ralf Karge]

**** Return 1's when one bit wide extract indexes outside array bounds.

**** Fixed compile warnings on 64-bit operating systems.

**** Fixed incorrect dependency in .d file when setting VERILATOR_BIN.


* Verilator 3.251 2004-09-09

**** Fixed parenthesis overflow in Microsoft Visual C++ [Renga Sundararajan]


* Verilator 3.250 2004-08-30

**   Support Microsoft Visual C++ [Renga Sundararajan]

***  SystemPerl 1.161+ is required.


* Verilator 3.241 2004-08-17

**   Support ,'s to separate multiple assignments. [Paul Nitza]

**** Fixed shift sign extension problem using non-GCC compilers.


* Verilator 3.240 2004-08-13

**   Verilator now uses 64 bit math where appropriate.
     Inputs and outputs of 33-64 bits wide to the C++ Verilated model must
     now be uint64_t's; SystemC has not changed, they will remain sc_bv's.
     This increases performance by ~ 9% on x86 machines, varying with how
     frequently 33-64 bit signals occur. Signals 9-16 bits wide are now
     stored as 16 bit shorts instead of longs, this aids cache packing.

**** Fixed SystemC compile error with feedthrus. [Paul Nitza]

**** Fixed concat value error introduced in 3.230.


* Verilator 3.230 2004-08-10

***  Added coverage output to test_sp example, SystemPerl 1.160+ is required.

**** Fixed time 0 value of signals. [Hans Van Antwerpen]
     Earlier versions would not evaluate some combinatorial signals
     until posedge/negedge blocks had been activated.

**** Fixed wide constant inputs to public submodules [Hans Van Antwerpen]

**** Fixed wide signal width extension bug.
     Only applies when width mismatch warnings were overridden.


* Verilator 3.220 2004-06-22

**   Many waveform tracing changes:

***  Tracing is now supported on C++ standalone simulations. [John Brownlee]

***  When tracing, SystemPerl 1.150 or newer is required.

***  When tracing, Verilator must be called with the --trace switch.

**** Added SystemPerl example to documentation. [John Brownlee]

**** Various Cygwin compilation fixes. [John Brownlee]


* Verilator 3.210 2004-04-01

**   Compiler optimization switches have changed
     See the BENCHMARKING section of the documentation.

***  With Verilog-Perl 2.3 or newer, Verilator supports SystemVerilog
     preprocessor extensions.

***  Added localparam. [Thomas Hawkins]

***  Added warnings for SystemVerilog reserved words.


* Verilator 3.203 2004-03-10

***  Notes and repairs for Solaris. [Fred Ma]


* Verilator 3.202 2004-01-27

**   The beta version is now the primary release. See below for many changes.
     If you have many problems, you may wish to try release 3.125.

***  Verilated::traceEverOn(true) must be called at time 0 if you will ever
     turn on tracing (waveform dumping) of signals. Future versions will
     need this switch to disable trace incompatible optimizations.

**** Fixed several tracing bugs

**** Added optimizations for common replication operations.


* Verilator 3.201-beta 2003-12-10

**   BETA VERSION, USE 3.124 for stable release!

**   Version 3.2XX includes a all new back-end.
     This includes automatic inlining, flattening of signals between
     hierarchy, and complete ordering of statements. This results in
     60-300% execution speedups, though less pretty C++ output. Even
     better results are possible using GCC 3.2.2 (part of Redhat 9.1), as
     GCC has fixed some optimization problems which Verilator exposes.

     If you are using `systemc_ctor, beware pointers to submodules are now
     initialized after the constructor is called for a module, to avoid
     segfaults, move statements that reference subcells into initial
     statements.

***  C++ Constructor that creates a verilog module may take a char* name.
     This name will be used to prefix any $display %m arguments, so users may
     distinguish between multiple Verilated modules in a single executable.


* Verilator 3.125 2004-01-27

**** Optimization of bit replications


* Verilator 3.124 2003-12-05

***  A optimized executable will be made by default, in addition to a debug
     executable. Invoking Verilator with --debug will pick the debug version.

**** Many minor invisible changes to support the next version.


* Verilator 3.123 2003-11-10

**** Wide bus performance enhancements.

**** Fixed function call bug when width warning suppressed. [Leon Wildman]

**** Fixed __DOT__ compile problem with funcs in last revision. [Leon Wildman]


* Verilator 3.122 2003-10-29

***  Modules which are accessed from external code now must be marked with
     /*verilator public_module*/ unless they already contain public signals.
     To enforce this, private cell names now have a string prepended.

**** Fixed replicated function calls in one statement. [Robert A. Clark]

**** Fixed function call bug when width warning suppressed. [Leon Wildman]


* Verilator 3.121 2003-09-29

***  Support multiplication over 32 bits. [Chris Boumenot]
     Also improved speed of addition and subtraction over 32 bits.

***  Detect bit selection out of range errors.

***  Detect integer width errors.

**** Fixed width problems on function arguments. [Robert A. Clark]


* Verilator 3.120 2003-09-24

***  $finish now exits the model (via vl_finish function).

***  Support inputs/outputs in tasks.

***  Support V2K "integer int = {INITIAL_VALUE};"

***  Ignore floating point delay values. [Robert A. Clark]

**** Ignore `celldefine, `endcelldefine, etc. [Robert A. Clark]

**** New optimizations on reduction operators.

**** Fixed converting "\ooo" into octal values.

**** Fixed $display("%x");


* Verilator 3.112 2003-09-16

**** Fixed functions in continuous assignments. [Robert A. Clark]

**** Fixed inlining of modules with 2-level deep outputs.


* Verilator 3.111 2003-09-15

**** Fixed declaration of functions before using that module. [Robert A. Clark]

**** Fixed module inlining bug with outputs.


* Verilator 3.110 2003-09-12

**   Support Verilog 2001 style input/output declarations. [Robert A. Clark]

***  Allow local vars in headers of function/tasks. [Leon Wildman]


* Verilator 3.109 2003-08-28

**   Added support for local variables in named begin blocks. [Leon Wildman]


* Verilator 3.108 2003-08-11

**   Added support for functions.

***  Signals 8 bits and shorter are now stored as chars
     instead of uint32_t's. This improves Dcache packing and
     improves performance by ~7%.

**** $display now usually results in a single VL_PRINT rather then many.

**** Many optimizations involving conditionals (?:)


* Verilator 3.107 2003-07-15

***  --private and --l2name are now the default,
     as this enables additional optimizations.
     Use --noprivate or --nol2name to get the older behavior.

***  Now support $display of binary and wide format data.

***  Added detection of incomplete case statements,
     and added related optimizations worth ~4%.

**** Work around flex bug in Redhat 8.0. [Eugene Weber]

**** Added some additional C++ reserved words.

**** Additional constant optimizations, ~5% speed improvement.


* Verilator 3.106 2003-06-17

** $c can now take multiple expressions as arguments.
   For example $c("foo","bar(",32+1,");") will insert "foobar(33);"
   This makes it easier to pass the values of signals.

** Several changes to support future versions that may have
   signal-eliminating optimizations. Users should try to use these switch
   on designs, they will become the default in later versions.

*** Added --private switch and /*verilator public*/ metacomment.
    This renames all signals so that compile errors will result if any
    signals referenced by C++ code are missing a /*verilator public*/
    metacomment.

*** With --l2name, the second level cell C++ cell is now named "v".
    Previously it was named based on the name of the verilog code. This
    means to get to signals, scope to "{topcell} ->v ->{mysignal}" instead
    of "{topcell} ->{verilogmod}. {mysignal}". This allows different
    modules to be substituted for the cell without requiring source
    changes.

**** Several cleanups for Redhat 8.0.


* Verilator 3.105 2003-05-08

**** Fixed more GCC 3.2 errors. [David Black]


* Verilator 3.104 2003-04-30

*** Indicate direction of ports with VL_IN and VL_OUT.

*** Allow $c32, etc, to specify width of the $c statement for VCS.

**** Fixed false "indent underflow" error inside `systemc_ctor sections.

**** Fixed missing ordering optimizations when outputs also used internally.

*** Numerous performance improvements, worth about 25%

**** Assign constant cell pins in initial blocks rather then every cycle.

**** Promote subcell's combo logic to sequential evaluation when possible.

**** Fixed GCC 3.2 compile errors. [Narayan Bhagavatula]


* Verilator 3.103 2003-01-28

**** Fixed missing model evaluation when clock generated several levels of
     hierarchy across from where it is used as a clock. [Richard Myers]

**** Fixed sign-extension bug introduced in 3.102.


* Verilator 3.102 2003-01-24

**** Fixed sign-extension of X/Z's ("32'hx")


* Verilator 3.101 2003-01-13

**** Fixed 'parameter FOO=#'bXXXX' [Richard Myers]

**** Allow spaces inside numbers ("32'h 1234") [Sam Gladstone]


* Verilator 3.100 2002-12-23

**   Support for simple tasks w/o vars or I/O. [Richard Myers]

**** Ignore DOS carriage returns in Linux files. [Richard Myers]


* Verilator 3.012 2002-12-18

**** Fixed parsing bug with casex statements containing case items
     with bit extracts of parameters. [Richard Myers]

**** Fixed bug which could cause writes of non-power-of-2 sized arrays to
     corrupt memory beyond the size of the array. [Dan Lussier]

**** Fixed bug which did not detect UNOPT problems caused by
     submodules. See the description in the verilator man page. [John Deroo]

**** Fixed compile with threaded Perl. [Ami Keren]


* Verilator 3.010 2002-11-03

*** Support SystemC 2.0.1. SystemPerl version 1.130 or newer is required.

**** Fixed bug with inlined modules under other inlined modules. [Scott
     Bleiweiss]


* Verilator 3.005 2002-10-21

**** Fixed X's in case (not casex/z) to constant propagate correctly.

**** Fixed missing include. [Kurachi]


* Verilator 3.004 2002-10-10

*** Added /* verilator module_inline */ and associated optimizations.

*** Allow /* verilator coverage_block_off */ in place of `coverage_block_off.
    This prevents problems with Emacs AUTORESET. [Ray Strouble]

**** Fixed `coverage_block_off also disabling subsequent blocks.

**** Fixed unrolling of loops with multiple simple statements.

**** Fixed compile warnings on newer GCC. [Kurachi]

**** Additional concatenation optimizations.


* Verilator 3.003 2002-09-13

*** Now compiles on Windows 2000 with Cygwin.

**** Fixed bug with pin assignments to wide memories.

**** Optimize wire assignments to constants.


* Verilator 3.002 2002-08-19

** First public release of version 3.


* Verilator 3.000 2002-08-03

** All new code base. Many changes too numerous to mention.

*** Approximately 4 times faster then Verilator 2.
*** Supports initial statements
*** Supports correct blocking/nonblocking assignments
*** Supports `defines across multiple modules
*** Optimizes call ordering, constant propagation, and dead code elimination.


* Verilator 2.1.8 2002-04-03

** All applications must now link against include/verilated.cpp

*** Paths specified to verilator_make should be absolute, or be formed
   to allow for execution in the object directory (prepend ../ to each path.)
   This allows relative filenames for makes which hash and cache dependencies.

**** Added warning when parameter constants are too large. [John Deroo]

**** Added warning when x/?'s used in non-casez statements.

**** Added warning when blocking assignments used in posedge blocks. [Dan Lussier]

**** Split evaluation function into clocked and non-clocked, 20% perf gain.


* Verilator 2.1.5 2001-12-01

** Added coverage analysis. In conjunction with SystemC provide line
   coverage reports, without SystemC, provide a hook to user written
   accumulation function. See --coverage option of verilator_make.

*** Relaxed multiply range checking

*** Support for constants up to 128 bits

*** Randomize values used when assigning to X's.

**** Added -guard option of internal testing.

**** Changed indentation in emitted code to be automatically generated.

**** Fixed corruption of assignments of signal over 32 bits with non-0 lsb.


* Verilator 2.1.4 2001-11-16

** Added $c("c_commands();");  for embedding arbitrary C code in Verilog.


* Verilator 2.1.3 2001-11-03

** Support for parameters.


* Verilator 2.1.2 2001-10-25

** Verilog Errors now reference the .v file rather then the .vpp file.

*** Support strings in assignments:  reg [31:0] foo = "STRG";

*** Support %m in format strings. Ripped out old $info support, use
    Verilog-Perl's vpm program instead.

*** Convert $stop to call of v_stop() which user can define.

**** Fixed bug where a==b==c would have wrong precedence rule.

**** Fixed bug where XNOR on odd-bit-widths (~^ or ^~) had bad value.


* Verilator 2.1.1 2001-05-17

** New test_sp directory for System-Perl (SystemC) top level instantiation
of the Verilated code, lower modules are still C++ code. (Experimental).

** New test_spp directory for Pure System-Perl (SystemC) where every module
is true SystemC code. (Experimental)

*** Input ports are now loaded by pointer reference into the sub-cell.
This is faster on I-386 machines, as the stack must be used when there are
a large number of parameters. Also, this simplifies debugging as the value
of input ports exists for tracing.

**** Many code cleanups towards standard C++ style conventions.


* Verilator 2.1.0 2001-05-08

**** Many code cleanups towards standard C++ style conventions.


* {Version history lost}


* Verilator 1.8 1996-07-08

** [Versions 0 to 1.8 were by Paul Wasson]

****  Fixed single bit in concat from instance output incorrect offset bug.


* Verilator 1.7 1996-05-20

****  Mask unused bits of DONTCAREs.


* Verilator 1.6 1996-05-13

*** Added fasttrace script


* Verilator 1.5 1996-01-09

*** Pass structure pointer into translated code,
    so multiple instances can use same functions.

**** Fixed static value concat on casex items.


* Verilator 1.1 1995-03-30

*** Bug fixes, added verimake_partial script, performance improvements.


* Verilator 1.0c 1994-09-30

*** Initial release of Verilator


* Verilator 0.0 1994-07-08

**** First code written.

----------------------------------------------------------------------

This uses outline mode in Emacs. See C-h m [M-x describe-mode].

Copyright 2001-2020 by Wilson Snyder. This program is free software; you
can redistribute it and/or modify it under the terms of either the GNU
Lesser General Public License Version 3 or the Perl Artistic License
Version 2.0.
SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0

Local variables:
mode: outline
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end:
