Add libgc to mono

svn path=/trunk/mono/; revision=35994

1 files changed, 67 insertions, 0 deletions

diff --git a/libgc/README.Mono b/libgc/README.Mono
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+This is a modified version of Boehm GC 6.1 for Mono.
+
+* There are two main changes to the upstream version:
+
+  - Makefile changes:
+
+    libgc has a lot of configurable options which are AC_DEFINE()d in its
+    configure.in.  To make it easier to build and bundle it with Mono, I
+    replaced most of the orignal configure.in and the makefiles with custom
+    versions which just define what we actually need for Mono.
+
+    This means that you can just run configure in this directory and it'll
+    do the right thing.  Later on, we'll just include this package in Mono
+    and use AC_CONFIG_SUBDIRS().
+
+  - Threading changes
+
+    The original libgc has several *_threads.c files for each possible threading
+    implementation.
+
+    For Mono, we're using a vtable
+
+        typedef struct
+        {
+                void (* initialize) (void);
+                void (* lock) (void);
+                void (* unlock) (void);
+                void (* stop_world) (void);
+                void (* push_thread_structures) (void);
+                void (* push_all_stacks) (void);
+                void (* start_world) (void);
+        } GCThreadFunctions;
+
+        extern GCThreadFunctions *gc_thread_vtable;
+
+    and a mono_threads.c file.
+
+  - Deleted files
+
+    Some files from the original distribution have been deleted in this version.
+    These are files which weren't actually linked into the library so they were not
+    needed.  When importing a new upstream version, you can either keep them removed
+    or just replace them with their new upstream versions.
+
+  - include/private/gc_locks.h
+
+    This file has been replaced with a custom version.
+
+    When importing a new upstream version, keep this custom version, ie. don't import the
+    new upstream gc_locks.h.
+
+* Importing a new upstream version
+
+  This is really simple.  Just import the new version to the vendor branch (LIBGC) in CVS
+  and then merge it into the main trunk.
+
+  To get a diff to the original version:
+
+        cvs diff -u -r LIBGC
+
+  When importing new upstream versions, don't import the new configure.in or any of the
+  Makefile.am's; they've been replaced by custom versions.  Just import all the new source
+  files and it should be fine.
+
+
+April 4th, 2003
+Martin Baulig <martin@ximian.com>