import gc6.1alpha5

gc/doc/README

@@ -9,8 +9,9 @@ Copyright (c) 1998 by Fergus Henderson.  All rights reserved.
 The files Makefile.am, and configure.in are
 Copyright (c) 2001 by Red Hat Inc. All rights reserved.
 
-The files config.guess and a few others are copyrighted by the Free
-Software Foundation.
+Several files supporting GNU-style builds are copyrighted by the Free
+Software Foundation, and carry a different license from that given
+below.
 
 THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
 OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
@@ -27,7 +28,7 @@ are GPL'ed, but with an exception that should cover all uses in the
 collector.  (If you are concerned about such things, I recommend you look
 at the notice in config.guess or ltmain.sh.)
 
-This is version 6.1alpha2 of a conservative garbage collector for C and C++.
+This is version 6.1alpha5 of a conservative garbage collector for C and C++.
 
 You might find a more recent version of this at
 

gc/doc/README.DGUX386

@@ -0,0 +1,215 @@
+    Garbage Collector (parallel iversion) for ix86 DG/UX Release R4.20MU07
+
+
+     *READ* the file README.QUICK.
+
+     You need the GCC-3.0.3 rev (DG/UX) compiler to build this tree.
+     This compiler has the new "dgux386" threads package implemented.
+     It also supports the switch "-pthread" needed to link correctly
+     the DG/UX's -lrte -lthread with -lgcc and the system's -lc. 
+     Finally we support parralleli-mark for the SMP DG/UX machines.
+     To build the garbage collector do:
+      
+      ./configure --enable-parallel-mark
+      make
+      make gctest
+
+     Before you run "gctest" you need to set your LD_LIBRARY_PATH
+     correctly so that "gctest" can find the shared library libgc.
+     Alternatively you can do a configuration
+
+      ./configure --enable-parallel-mark --disable-shared
+  
+     to build only the static version of libgc.
+  
+     To enable debugging messages please do:
+     1) Add the "--enable-full-debug" flag during configuration. 
+     2) Edit the file linux-threads.c and uncommnect the line:
+
+     /* #define DEBUG_THREADS 1 */ to ---> 
+
+     #define DEBUG_THREADS 1
+
+     Then give "make" as usual.
+    
+     In a machine with 4 CPUs (my own machine) the option parallel
+     mark (aka --enable-parallel-mark) makes a BIG difference.
+
+     Takis Psarogiannakopoulos
+     University of Cambridge
+     Centre for Mathematical Sciences
+     Department of Pure Mathematics
+     Wilberforce Road
+     Cambridge CB3 0WB ,UK , <takis@XFree86.Org>
+     January 2002
+
+
+Note (HB):
+     The integration of this patch is currently not complete.
+     The following patches against 6.1alpha3 where hard to move
+     to alpha4, and are not integrated.  There may also be minor
+     problems with stylistic corrections made by me.
+
+
+--- ltconfig.ORIG	Mon Jan 28 20:22:18 2002
++++ ltconfig	Mon Jan 28 20:44:00 2002
+@@ -689,6 +689,11 @@
+        pic_flag=-Kconform_pic
+     fi
+     ;;
++  dgux*)
++    pic_flag='-fPIC'
++    link_static='-Bstatic'
++    wl='-Wl,'
++    ;;
+   *)
+     pic_flag='-fPIC'
+     ;;
+@@ -718,6 +723,12 @@
+     # We can build DLLs from non-PIC.
+     ;;
+ 
++  dgux*)
++    pic_flag='-KPIC'
++    link_static='-Bstatic'
++    wl='-Wl,'
++    ;;
++
+   osf3* | osf4* | osf5*)
+     # All OSF/1 code is PIC.
+     wl='-Wl,'
+@@ -1154,6 +1165,22 @@
+     fi
+     ;;
+ 
++  dgux*)
++    ld_shlibs=yes
++    # For both C/C++ ommit the deplibs. This is because we relying on the fact
++    # that compilation of execitables will put them in correct order
++    # in any case and sometimes are wrong when listed as deplibs (or missing some deplibs)
++    # However when GNU ld and --whole-archive needs to be used we have the problem
++    # that if the -fPIC *_s.a archive is linked through deplibs list we ommiting crucial
++    # .lo/.o files from the created shared lib. This I think is not the case here.
++    archive_cmds='$CC -shared -h $soname -o $lib $libobjs $linkopts'
++    thread_safe_flag_spec='-pthread'
++    wlarc=
++    hardcode_libdir_flag_spec='-L$libdir'
++    hardcode_shlibpath_var=no
++    ac_cv_archive_cmds_needs_lc=no
++    ;;
++
+   cygwin* | mingw*)
+     # hardcode_libdir_flag_spec is actually meaningless, as there is
+     # no search path for DLLs.
+@@ -1497,7 +1524,7 @@
+     ;;
+ 
+   dgux*)
+-    archive_cmds='$LD -G -h $soname -o $lib $libobjs $deplibs $linkopts'
++    archive_cmds='$CC -shared -h $soname -o $lib $libobjs $linkopts'
+     hardcode_libdir_flag_spec='-L$libdir'
+     hardcode_shlibpath_var=no
+     ;;
+@@ -2092,12 +2119,17 @@
+   ;;
+ 
+ dgux*)
+-  version_type=linux
++  version_type=dgux
+   need_lib_prefix=no
+   need_version=no
+-  library_names_spec='${libname}${release}.so$versuffix ${libname}${release}.so$major $libname.so'
+-  soname_spec='${libname}${release}.so$major'
++  library_names_spec='$libname.so$versuffix'
++  soname_spec='$libname.so$versuffix'
+   shlibpath_var=LD_LIBRARY_PATH
++  thread_safe_flag_spec='-pthread'
++  wlarc=
++  hardcode_libdir_flag_spec='-L$libdir'
++  hardcode_shlibpath_var=no
++  ac_cv_archive_cmds_needs_lc=no
+   ;;
+ 
+ sysv4*MP*)
+
+
+--- ltmain.sh.ORIG	Mon Jan 28 20:31:18 2002
++++ ltmain.sh	Tue Jan 29 00:11:29 2002
+@@ -1072,11 +1072,38 @@
+ 	esac
+ 	;;
+ 
++      -thread*)
++	# DG/UX GCC 2.95.x, 3.x.x rev (DG/UX) links -lthread
++	# with the switch -threads
++	if test "$arg" = "-threads"; then
++	  case "$host" in
++	  i[3456]86-*-dgux*)
++	    deplibs="$deplibs $arg"
++	    continue
++	    ;;
++	  esac
++	fi
++	;;
++
++      -pthread*)
++	# DG/UX GCC 2.95.x, 3.x.x rev (DG/UX) links -lthread
++	# with the switch -pthread
++	if test "$arg" = "-pthread"; then
++	  case "$host" in
++	  i[3456]86-*-dgux*)
++	    deplibs="$deplibs $arg"
++	    continue
++	    ;;
++	  esac
++	fi
++	;;
++
+       -l*)
+ 	if test "$arg" = "-lc"; then
+ 	  case "$host" in
+-	  *-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos*)
++	  *-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos* | i[3456]86-*-dgux*)
+ 	    # These systems don't actually have c library (as such)
++	    # It is wrong in DG/UX to add -lc when creating shared/dynamic objs/libs
+ 	    continue
+ 	    ;;
+ 	  esac
+@@ -1248,6 +1275,12 @@
+ 	  temp_deplibs=
+ 	  for deplib in $dependency_libs; do
+ 	    case "$deplib" in
++	    -thread*)
++		 temp_deplibs="$temp_deplibs $deplib"
++		 ;;
++	    -pthread)
++		 temp_deplibs="$temp_deplibs $deplib"
++		 ;;
+ 	    -R*) temp_xrpath=`$echo "X$deplib" | $Xsed -e 's/^-R//'`
+ 		 case " $rpath $xrpath " in
+ 		 *" $temp_xrpath "*) ;;
+@@ -1709,6 +1742,13 @@
+ 	  done
+ 	  ;;
+ 
++	dgux)
++	  # Leave mostly blank for DG/UX
++	  major=
++	  versuffix=".$current.$revision";
++	  verstring=
++	  ;;
++
+ 	linux)
+ 	  major=.`expr $current - $age`
+ 	  versuffix="$major.$age.$revision"
+@@ -1792,8 +1832,9 @@
+ 
+ 	dependency_libs="$deplibs"
+ 	case "$host" in
+-	*-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos*)
++	*-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos* | i[3456]86-*-dgux*)
+ 	  # these systems don't actually have a c library (as such)!
++	  # It is wrong in DG/UX to add -lc when creating shared/dynamic objs/libs
+ 	  ;;
+ 	*)
+ 	  # Add libc to deplibs on all other systems.

gc/doc/README.arm.cross

@@ -0,0 +1,68 @@
+From: Margaret Fleck
+
+Here's the key details of what worked for me, in case anyone else needs them.
+There may well be better ways to do some of this, but ....
+   -- Margaret
+
+
+The badge4 has a StrongArm-1110 processor and a StrongArm-1111 coprocessor.  
+
+Assume that the garbage collector distribution is unpacked into /home/arm/gc6.0,
+which is visible to both the ARM machine and a linux desktop (e.g. via NFS mounting).
+
+Assume that you have a file /home/arm/config.site with contents something like the
+example attached below.  Notice that our local ARM toolchain lives in
+/skiff/local.
+
+Go to /home/arm/gc6.0 directory.  Do
+  CONFIG_SITE=/home/arm/config.site ./configure --target=arm-linux
+--prefix=/home/arm/gc6.0
+
+On your desktop, do:
+   make
+   make install
+The main garbage collector library should now be in ../gc6.0/lib/libgc.so.  
+
+To test the garbage collector, first do the following on your desktop
+   make gctest
+   ./gctest
+Then do the following on the ARM machine
+   cd .libs
+   ./lt-gctest
+
+Do not try to do "make test" (the usual way of running the test
+program).  This does not work and seems to erase some of the important
+files.
+
+The gctest program claims to have succeeded.  Haven't run any further tests
+with it, though I'll be doing so in the near future.
+
+-------------------------------
+# config.site for configure
+
+# Modified from the one provided by Bradley D. LaRonde
+# Edited by Andrej Cedilnik <acedil1@csee.umbc.edu>
+# Used some of solutions by Tilman Vogel <Tilman.Vogel@web.de>
+# Ported for iPAQ Familiar by Oliver Kurth <oliver.kurth@innominate.com>
+# Further modified by Margaret Fleck for the badge4
+
+HOSTCC=gcc
+
+# Names of the cross-compilers
+CC=/skiff/local/bin/arm-linux-gcc
+CXX=/skiff/local/bin/arm-linux-gcc
+
+# The cross compiler specific options
+CFLAGS="-O2 -fno-exceptions"
+CXXFLAGS="-O2 -fno-exceptions"
+CPPFLAGS="-O2 -fno-exceptions"
+LDFLAGS=""
+
+# Some other programs
+AR=/skiff/local/bin/arm-linux-ar
+RANLIB=/skiff/local/bin/arm-linux-ranlib
+NM=/skiff/local/bin/arm-linux-nm
+ac_cv_path_NM=/skiff/local/bin/arm-linux-nm
+ac_cv_func_setpgrp_void=yes
+x_includes=/skiff/local/arm-linux/include/X11
+x_libraries=/skiff/local/arm-linux/lib/X11

gc/doc/README.changes

@@ -1413,7 +1413,8 @@ Since 6.0:
    less common thread implementations, since some of the original code
    didn't stand up to close scrutiny.  Support for the next pthreads
    implementation should be easier to add.
-Since 6.0alpha1:
+
+Since 6.1alpha1:
  - No longer wrap read by default in multithreaded applications.  It was
    pointed out on the libgcj list that this holds the allocation lock for
    way too long if the read blocks.  For now, reads into the heap are
@@ -1425,7 +1426,8 @@ Since 6.0alpha1:
  - Added printing of stop-the-world GC times if GC_PRINT_STATS environment
    variable is set.
  - The calloc definition in leak_detector.h was missing parentheses, and
-   realloc was missing a second argument to GC_REALLOC.  (Thanks to Elrond.)
+   realloc was missing a second argument to GC_REALLOC.
+   (Thanks to Elrond (elrond<at>samba-tng.org).)
  - Added GC_PRINT_BACK_HEIGHT environment variable and associated
    code, mostly in the new file backgraph.c.  See doc/README.environment.
  - Added -DUSE_GLOBAL_ALLOC to work around a Windows NT issue.  (Thanks to
@@ -1435,11 +1437,202 @@ Since 6.0alpha1:
    holes in the data segment.  (Thanks to Hironori Sakamoto.)
  - Changed the order in which GC_push_roots and friends push things onto
    the mark stack.  GC_push_all calls need to come first, since we can't
-   necessarily recovere if thos overflow the mark stack.  (Thanks to
+   necessarily recovere if those overflow the mark stack.  (Thanks to
    Matthew Flatt for tracking down the problem.)
+ - Some minor cleanups to mostly support the Intel compiler on Linux/IA64.
+
+Since 6.1 alpha2:
+ - Minor cleanup on the gcconfig.h section for SPARC.
+ - Minor fix to support Intel compiler for I386/Linux. (Thanks to Sven
+   Hartrumpf.)
+ - Added SPARC V9 (64-bit) support.  (Thanks to Jeff Sturm.)
+ - Restructured the way in which we determine whether or not to keep
+   call stacks for debug allocation.  By default SAVE_CALL_COUNT is
+   now zero on all platforms.  Added SAVE_CALL_NARGS parameters.
+   If possible, use execinfo.h to capture call stack.  (This should
+   add support for a number of new platforms, though often at
+   considerable runtime expense.)
+ - Try to print symbolic information for call stacks.  On Linux, we
+   do this with a combination of execinfo.h and running addr2line in
+   a separate process.  This is both much more expensive and much more
+   useful.  Amazingly, it seems to be fast enough for most purposes.
+ - Redefined strdup if -DREDIRECT_MALLOC is given.
+ - Changed incremental collector and MPROTECT_VDB implementation so that,
+   under favorable conditions, pointerfree objects are not protected.
+   Added GC_incremental_protection_needs() to determine ahead of time whether
+   pointerfree objects may be protected.  Replaced GC_write_hint() with
+   GC_remove_protection().
+ - Added test for GC_ENABLE_INCREMENTAL environment variable.
+ - Made GC_time_limit runtime configurable.  Added GC_PAUSE_TIME_TARGET
+   environment variable.
+ - Eliminated GC_page_sz, a duplicate of GC_page_size.
+ - Caused the Solaris and Irix thread creation primitives to call
+   GC_init_inner().
+ 
+Since 6.1alpha3:
+ - Fixed typo in sparc_mach_dep.S, preventing the 64-bit version from
+   building.  Increased 64-bit heap size limit in test.c slightly, since
+   a functional SPARC collector seems to slightly exceed the old limits.
+   (Thanks again to Jeff Sturm.)
+ - Use NPRGREG in solaris_threads.c, thus printing all registers if things
+   go wrong.
+ - Added GC_MARKERS environment variable to allow use of a single marker
+   thread on an MP without confusing the lock implementation.
+ - Collect much less aggressively in incremental mode with GC_TIME_UNLIMITED.
+   This is really a purely generational mode, and we can afford to 
+   postpone the collection until the heap is (nearly) full.
+ - Remove read() wrapper for MPROTECT_VDB.  It was causing more harm than
+   good.  It is often no longer needed if system calls avoid writing to
+   pointerfull heap objects.
+ - Fix MACOSX test in gcconfig.h. (Thanks to John Clements.)
+ - Change GC_test_and_set so that it consistently has one argument.
+   Add spaces to ::: in powerpc assembly code in gc_locks.h.
+   (Thanks to Ryan Murray.)
+ - Fixed a formatting error in dbg_mlc.c.  Added prototype to GC_abort()
+   declaration.   (Thanks to Michael Smith.)
+ - Removed "source" argument to GC_find_start().  Eliminate GC_FIND_START().
+ - Added win32 recognition code in configure.in.  Changed some of the
+   dllimport/export defines in gc.h.  (Thanks to Adam Megacz.)
+ - GC_malloc_many didn't set hb_last_reclaimed when it called 
+   GC_reclaim_generic.  (I'm not sure this matters much, but ...)
+ - Allocating uncollectable objects with debug information sometimes
+   allocated objects that were one byte too small, since uncollectable
+   objects don't have the extra byte added at the end.  (Thanks to
+   Wink Saville for pointing this out.)
+ - Added a bit more assertion checking to make sure that gcj objects
+   on free lists never have a nonzero second word.
+ - Replaced BCC_MAKEFILE with an up-to-date one.  (Thanks to 
+   Andre Leiradella.)
+ - Upgraded libtool, cinfigure.in and some related files to hopefully
+   support NetBSD/SPARC.  (Thanks to Adrian Bunk.)  Unfortunately,
+   libtool 1.4.2 seemed to be buggy due to missing quotes in several
+   "test" invocations.  Fixed those in the ltmain.sh script.
+ - Some win32-specific patches, including the introduction of
+   GC_CreateThread.  (Thanks to Adam Megacz.)
+ - Merged in gcj changes from Anthony Green to support embedded systems.
+ - Tried to consistently rename preprocessed assembly files with a capital
+   .S extension.
+ - Use alpha_mach_dep.S on ALPHA again.  It doesn't really matter, but this
+   makes our distribution consistent with the gcc one, avoiding future merge
+   problems.
+ - Move GET_MEM definition into gcconfig.h.  Include gcconfig.h slightly
+   later in gc_priv.h to avoid forward references to ptr_t.
+ - Add some testing of local allocation to test.c.
+ - Change definition of INVALID_QTID in specific.h.  The -1 value was used
+   inconsistently, and too likely to collide with a valid stack address.
+   Some general clean-up of specific.[ch].  Added assertions.  (Thanks
+   to Michael Smith for tracking down an intermittent bug to this
+   general area.  I'm not sure it has been squashed yet, however.)
+ - On Pthread systems it was not safe to call GC_malloc() between fork()
+   and exec().  According to the applicable standards, it doesn't appear
+   to be safe to call malloc() or many other libc functions either, thus
+   it's not clear this is fixable.  Added experimental support for
+   -DHANDLE_FORK in linux_threads.c which tries to support it.  It may
+   succeed if libc does the right thing.  I'm not sure whether it does.
+   (Thanks to Kenneth Schalk for pointing out this issue.)
+ - Documented thread local allocation primitives to require an
+   explicit GC_init call.  GC_init_parallel is no longer declared to
+   be a constructor function, since that isn't portable and often
+   seems to lead to initialization order problems.
+ - Changed gc_cpp.cc and gc_cpp.h in one more attempt to make them
+   compatible with Visual C++ 6.  (Thanks to Wink Saville for the
+   patch.)
+ - Some more patches for Linux on HP PA-RISC.
+ - Added include/gc_allocator.h.  It implements (hopefully) standard
+   conforming (as opposed to SGI-style) allocators that allocate
+   collectable (gc_allocator) or GC-traceable, but not collectable
+   (traceable_allocator) objects.  This borrows heavily from libstc++,
+   which borrows heavily from the SGI implementation, this part of
+   which was written by Matt Austern.  Changed test_cpp.cc to very
+   minimally test this.
+ - On Linux/X86, retry mmap with a different start argument.  That should
+   allow the collector to use more (closer to 3GB) of the address space.
+   (Thanks to Jeffrey Mark Siskind for tracking this down.)
+ - Force 64 bit alignment with GCJ support.  (Reflects Bryce McKinley's
+   patch to the gcc tree.)
+ - Refined the choice of sa_handler vs. sa_sigaction in GC_dirty_init
+   to accomodate some glibc5 systems.  (Thanks to Dan Fandrich for the
+   patch.)
+ - Compensated for the fact that current versions of glibc set
+   __libc_stack_end incorrectly on Linux/IA64 while initialization code
+   is running.  This could cause the collector to miss 16 bytes of
+   the memory stack if GC_malloc or friends where called before main().
+ - Mostly integrated Takis Psarogiannakopoulos' port to DG/UX Inix 86.
+   This will probably take another iteration to work, since his
+   patch conflicted with the libtool upgrade. 
+ - Added README.arm.cross containing some information about cross-
+   compiling to an ARM processor from Margaret Fleck.
+
+Since 6.1alpha4:
+ - Added GC_finalizer_mem_freed, and changed some of the code that
+   decided on heap expansion to look at it.  Memory explicitly
+   deallocated by finalizers essentially needs to be counted as reclaimed
+   by the GC.  Otherwise there are cases in which the heap can grow
+   unboundedly.  (Thanks to Mark Reichert for the test case.)
+ - Integrated Adam Megacz patches to not scan dynamic libraries if
+   we are compiling with gcc on win32.  Otherwise we need structured
+   exception handling to deal with asynchronously unmapped root
+   segments, and gcc doesn't directly support that.
+ - Integrated Anthony Green's patch to support Wine.
+ - GC_OPERATOR_NEW_ARRAY was misspelled OPERATOR_NEW_ARRAY in several
+   places, including gc_cpp.cc.  (Thanks to Wink Saville for pointing
+   this out.)
+ - Integrated Loren James Rittle's Alpha FreeBSD patches.  In
+   response to Richard Henderson's suggestion, these also
+   changed the declarations of symbols like _end on many platforms to
+   that they wouldn't mistakenly be declared as short data symbols.
+ - Integrated changes from the Debian distribution.  (Thanks to Ryan Murray
+   for pointing these out.)  Fix C++ comments in POWERPC port.  Add ARM32
+   incremental GC support.  Get rid of USE_GENERIC_PUSH_REGS for alpha/Linux,
+   this time for real.  Use va_copy to get rid of cord printf problems
+   (finally).
+ - Close file descriptor used to count cpus.  Thanks to Jeff Sturm for
+   pointing out the omission.
+ - Don't just drop gcj free lists in GC_start_reclaim, since that can
+   eventually cause the marker to see a bogus mark descriptor in the 
+   dropped objects.  The usual symptom was a very intermittent segmentation
+   fault in the marker.  This mattered only if one of the GC_gcj_malloc
+   variants was used.  (Thanks to Michael Smith, Jeff Sturm, Bryce
+   McKinley and Tom Tromey for helping to track this down.)
+ - Fixed Linux and Solaris/64 SPARC configuration.  (Thanks to David Miller,
+   Jeff Sturm, Tom Tromey, and Christian Joensson.)
+ - Fixed a typo in strdup definition.  (Thanks to Gerard A Allan.)
+ - Changed Makefile.direct to invoke $(CC) to assemble alpha_mach_dep.S.
+   This is needed on Linux.  I'm not sure whether it's better or worse
+   on Tru64.
+ - Changed gc_cpp.h once more to declare operator new and friends only in
+   a Microsoft environment.  This may need further fine tuning.  (Thanks to
+   Johannes Schmidt for pointing out that the older code breaks on gcc3.0.4.)
+ - Don't ever override strdup if it's already macro defined.  (Thanks to
+   Adnan Ali for pointing out the problem.)
+ - Changed gc_cpp.h yet again to also overload placement new.  Due to the
+   C++ overloading rules, the other overloaded new operations otherwise hide
+   placement new, which causes many STL uses to break.  (Thanks to Reza
+   Shahidi for reporting this, and to Matt Austern for proposing a fix.)
+ - Integrated cygwin pthreads support from Dan Bonachea.
+ - Turn on DYNAMIC_LOADING for NetBSD.  (Thanks to Krister Walfridsson.)
+ - Changed printing code to print more complete GC times.
+ - Applied Mark Mitchell's Irix patch to correct some bitrot.
+ - Clarified which object-printing routines in dbg_mlc.c should hold
+   the allocation lock.  Restructured the code to allow reasonable object
+   printing with -DREDIRECT_MALLOC.
+ - Fix the Linux mmap code to always start with 0x1000 as the initial hint.
+   Minor patches for 64-bit AIX, particularly to STACKBOTTOM.
+   (Thanks again to Jeffrey Mark Siskind.)
+ - Renamed "SUSPENDED" flag for Solaris threads support to avoid a conflict
+   with a system header. (Thanks to Philp Brown.)
  
 
 To do:
+ - --enable-redirect-malloc is mostly untested and known not to work
+   on some platforms. 
+ - The win32 collector ends up tracing some (most?) objects allocated with
+   the system allocator, in spite if the fact that it tries not to.
+   This costs time and space, though it remains correct.
+   We need a way to identify memory regions used by the system malloc(),
+   or an alternate way to locate dll data areas.  A very partial
+   workaround is to use GC_malloc_atomic_uncollectable() instead of
+   the system malloc() for most allocation.
  - There seem to be outstanding issues on Solaris/X86, possibly with
    finding the data segment starting address.  Information/patches would
    be appreciated.
@@ -1457,7 +1650,4 @@ To do:
  - Incremental collector should handle large objects better.  Currently,
    it looks like the whole object is treated as dirty if any part of it
    is.
- - Cord/cordprnt.c doesn't build on a few platforms (notably PowerPC), since
-   we make some unwarranted assumptions about how varargs are handled.  This
-   currently makes the cord-aware versions of printf unusable on some platforms.
-   Fixing this is unfortunately not trivial.
+ 

gc/doc/README.environment

@@ -27,10 +27,26 @@ GC_PRINT_ADDRESS_MAP - Linux only.  Dump /proc/self/maps, i.e. various address
 GC_NPROCS=<n> - Linux w/threads only.  Explicitly sets the number of processors
 	        that the GC should expect to use.  Note that setting this to 1
 		when multiple processors are available will preserve
-		correctness, but may lead to really horrible performance.
+		correctness, but may lead to really horrible performance,
+		since the lock implementation will immediately yield without
+		first spinning.
+
+GC_MARKERS=<n> - Linux w/threads and parallel marker only.  Set the number
+		of marker threads.  This is normaly set to the number of
+		processors.  It is safer to adjust GC_MARKERS than GC_NPROCS,
+		since GC_MARKERS has no impact on the lock implementation.
 
 GC_NO_BLACKLIST_WARNING - Prevents the collector from issuing
-		"Needed to allocate blacklisted block at ..." warnings.
+		warnings about allocations of very large blocks.
+		Deprecated.  Use GC_LARGE_ALLOC_WARN_INTERVAL instead.
+
+GC_LARGE_ALLOC_WARN_INTERVAL=<n> - Print every nth warning about very large
+		block allocations, starting with the nth one.  Small values
+		of n are generally benign, in that a bounded number of
+		such warnings generally indicate at most a bounded leak.
+		For best results it should be set at 1 during testing.
+		Default is 5.  Very large numbers effectively disable the
+		warning.
 
 GC_IGNORE_GCJ_INFO - Ignore the type descriptors implicitly supplied by
 		     GC_gcj_malloc and friends.  This is useful for debugging
@@ -57,6 +73,26 @@ The following turn on runtime flags that are also program settable.  Checked
 only during initialization.  We expect that they will usually be set through
 other means, but this may help with debugging and testing:
 
+GC_ENABLE_INCREMENTAL - Turn on incremental collection at startup.  Note that,
+		     depending on platform and collector configuration, this
+		     may involve write protecting pieces of the heap to
+		     track modifications.  These pieces may include pointerfree
+		     objects or not.  Although this is intended to be
+		     transparent, it may cause unintended system call failures.
+		     Use with caution.
+
+GC_PAUSE_TIME_TARGET - Set the desired garbage collector pause time in msecs.
+		     This only has an effect if incremental collection is
+		     enabled.  If a collection requires appreciably more time
+		     than this, the client will be restarted, and the collector
+		     will need to do additional work to compensate.  The
+		     special value "999999" indicates that pause time is
+		     unlimited, and the incremental collector will behave
+		     completely like a simple generational collector.  If
+		     the collector is configured for parallel marking, and
+		     run on a multiprocessor, incremental collection should
+		     only be used with unlimited pause time.
+
 GC_FIND_LEAK - Turns on GC_find_leak and thus leak detection.
 
 GC_ALL_INTERIOR_POINTERS - Turns on GC_all_interior_pointers and thus interior

gc/doc/README.ews4800

@@ -73,3 +73,9 @@ GC on EWS4800
 --
 Hironori SAKAMOTO <hsaka@mth.biglobe.ne.jp>
 
+
+When using the new "configure; make" build process, please
+run configure with the --disable-shared option.  "Make check" does not
+yet pass with dynamic libraries.  Ther reasons for that are not yet
+understood.  (HB, paraphrasing message from Hironori SAKAMOTO.)
+

gc/doc/README.win32

@@ -21,6 +21,13 @@ registrations are ignored, but not terribly quickly.)
 pointers.  And the VirtualQuery call has different semantics under
 the two systems, and under different versions of win32s.)
 
+Win32 applications compiled with some flavor of gcc currently behave
+like win32s applications, in that dynamic library data segments are
+not scanned.  (Gcc does not directly support Microsoft's "structured
+exception handling".  It turns out that use of this feature is
+unavoidable if you scan arbirtray memory segments obtained from
+VirtualQuery.)
+
 The collector test program "gctest" is linked as a GUI application,
 but does not open any windows.  Its output appears in the file
 "gc.log".  It may be started from the file manager.  The hour glass
@@ -50,7 +57,8 @@ This appears to cause problems under Windows NT and Windows 2000 (but
 not Windows 95/98) if the memory is later passed to CreateDIBitmap.
 To work around this problem, build the collector with -DUSE_GLOBAL_ALLOC.
 This is currently incompatible with -DUSE_MUNMAP.  (Thanks to Jonathan
-Clark for tracking this down.)
+Clark for tracking this down.  There's some chance this may be fixed
+in 6.1alpha4, since we now separate heap sections with an unused page.)
 
 For Microsoft development tools, rename NT_MAKEFILE as
 MAKEFILE.  (Make sure that the CPU environment variable is defined
@@ -64,7 +72,7 @@ absence of thread support).
 For GNU-win32, use the regular makefile, possibly after uncommenting
 the line "include Makefile.DLLs".  The latter should be necessary only
 if you want to package the collector as a DLL.  The GNU-win32 port is
-believed to work only for b18, not b19, probably dues to linker changes
+believed to work only for b18, not b19, probably due to linker changes
 in b19.  This is probably fixable with a different definition of
 DATASTART and DATAEND in gcconfig.h.