This directory contains various versions of the Boehm-Demers-Weiser conservative garbage collector. The collector can be used as a garbage collecting replacement for C malloc or C++ New. It is also used by a number of programming language implementations that use C as intermediate code. It may also be used as a leak detector for C or C++ programs, though that is not its primary goal. The file gc.tar.Z is a copy of the version currently considered most stable. This may not be the latest version. However the latest version will often support additional target platforms or features. See the README file in the distribution for more details. The file boecha.ps.Z contains a reprint of the paper "A Proposal for Garbage-Collector-Safe C Compilation", by Boehm and Chase. It originally appeared in the December 1992 issue of the Journal of C Language Translation. We thank John Levine and JCLT for allowing us to make the paper available electronically, and providing PostScript for the final version. (In retrospect, this paper did not pay enough attention to the case in which all interior pointers are considered valid. Some of the stated assumptions are unnecessarily restricitive, and simpler techniques suffice.) Hans-J. Boehm (boehm@parc.xerox.com)