2007-02-14 Andreas Tobler <a.tobler@schweiz.org>

	* configure.ac: Introduce extra_ldflags_libgc. Use it for Darwin.
	* configure: Regenerate.
	* Makefile.am (libgc_la_LDFLAGS): Use extra_ldflags_libgc.
	* Makefile.in: Regenerate.
	* include/private/gcconfig.h: Enable MPROTECT_VDB for all Darwin
	targets. Remove comments.
	Prepare ppc64 support for Darwin.

diff --git a/ChangeLog b/ChangeLog
index fced1e2c3b42d6edc68d983cc191ecd1761c2df9..e1fc871b0521e020df5aa8bf8f70a56fe2d2740b 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2007-02-14  Andreas Tobler  <a.tobler@schweiz.org>
+
+       * configure.ac: Introduce extra_ldflags_libgc. Use it for Darwin.
+       * configure: Regenerate.
+       * Makefile.am (libgc_la_LDFLAGS): Use extra_ldflags_libgc.
+       * Makefile.in: Regenerate.
+       * include/private/gcconfig.h: Enable MPROTECT_VDB for all Darwin
+       targets. Remove comments.
+       Prepare ppc64 support for Darwin.
+
 2007-01-29  Andreas Tobler  <a.tobler@schweiz.org>
 
        * darwin_stop_world.c: Clean up and reformat code.

diff --git a/Makefile.am b/Makefile.am
index 05af211fc83fde964d9cc517bd010a3b034b3ccc..f4ab1aa8751ff8ce5c6611a7e828678999c13438 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -87,11 +87,13 @@ if NEED_ATOMIC_OPS_ASM
 libgc_la_SOURCES += atomic_ops_sysdeps.S
 endif
 
+extra_ldflags_libgc = @extra_ldflags_libgc@
+
 # Include THREADDLLIBS here to ensure that the correct versions of
 # linuxthread semaphore functions get linked:
 libgc_la_LIBADD = @addobjs@ $(THREADDLLIBS) $(UNWINDLIBS)
 libgc_la_DEPENDENCIES = @addobjs@
-libgc_la_LDFLAGS = -version-info 1:2:0
+libgc_la_LDFLAGS = $(extra_ldflags_libgc) -version-info 1:2:0
 
 EXTRA_libgc_la_SOURCES = alpha_mach_dep.S \
     mips_sgi_mach_dep.s mips_ultrix_mach_dep.s \

diff --git a/Makefile.in b/Makefile.in
index 01a6c3330f21f4a365b9d74b481a725b97c84439..b39ab6b88b436f4db922865a56dbf95445add7b5 100644 (file)
--- a/Makefile.in
+++ b/Makefile.in
@@ -103,9 +103,9 @@ DIST_COMMON = $(am__configure_deps) $(am__pkginclude_HEADERS_DIST) \
        $(srcdir)/Makefile.am $(srcdir)/Makefile.in \
        $(srcdir)/bdw-gc.pc.in $(srcdir)/cord/cord.am \
        $(srcdir)/doc/doc.am $(srcdir)/include/include.am \
-       $(srcdir)/tests/tests.am $(top_srcdir)/configure compile \
-       config.guess config.sub depcomp install-sh ltmain.sh missing \
-       mkinstalldirs
+       $(srcdir)/tests/tests.am $(top_srcdir)/configure ChangeLog \
+       compile config.guess config.sub depcomp install-sh ltmain.sh \
+       missing mkinstalldirs
 
 #TESTS += tracetest$(EXEEXT)
 #check_PROGRAMS += tracetest
@@ -215,20 +215,20 @@ LTCCASCOMPILE = $(LIBTOOL) --mode=compile $(CCAS) $(AM_CCASFLAGS) \
        $(CCASFLAGS)
 COMPILE = $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
        $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS)
-LTCOMPILE = $(LIBTOOL) --mode=compile $(CC) $(DEFS) \
+LTCOMPILE = $(LIBTOOL) --tag=CC --mode=compile $(CC) $(DEFS) \
        $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) \
        $(AM_CFLAGS) $(CFLAGS)
 CCLD = $(CC)
-LINK = $(LIBTOOL) --mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) \
+LINK = $(LIBTOOL) --tag=CC --mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) \
        $(AM_LDFLAGS) $(LDFLAGS) -o $@
 CXXCOMPILE = $(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \
        $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS)
-LTCXXCOMPILE = $(LIBTOOL) --mode=compile $(CXX) $(DEFS) \
+LTCXXCOMPILE = $(LIBTOOL) --tag=CXX --mode=compile $(CXX) $(DEFS) \
        $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) \
        $(AM_CXXFLAGS) $(CXXFLAGS)
 CXXLD = $(CXX)
-CXXLINK = $(LIBTOOL) --mode=link $(CXXLD) $(AM_CXXFLAGS) $(CXXFLAGS) \
-       $(AM_LDFLAGS) $(LDFLAGS) -o $@
+CXXLINK = $(LIBTOOL) --tag=CXX --mode=link $(CXXLD) $(AM_CXXFLAGS) \
+       $(CXXFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
 SOURCES = $(libcord_la_SOURCES) $(libgc_la_SOURCES) \
        $(EXTRA_libgc_la_SOURCES) $(libgccpp_la_SOURCES) \
        $(gctest_SOURCES) $(leaktest_SOURCES) $(middletest_SOURCES) \
@@ -293,6 +293,7 @@ CPLUSPLUS_TRUE = @CPLUSPLUS_TRUE@
 CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
 CXX = @CXX@
+CXXCPP = @CXXCPP@
 CXXDEPMODE = @CXXDEPMODE@
 CXXFLAGS = @CXXFLAGS@
 CXXINCLUDES = @CXXINCLUDES@
@@ -310,8 +311,11 @@ ENABLE_GCJ_SUPPORT_FALSE = @ENABLE_GCJ_SUPPORT_FALSE@
 ENABLE_GCJ_SUPPORT_TRUE = @ENABLE_GCJ_SUPPORT_TRUE@
 EXEEXT = @EXEEXT@
 EXTRA_TEST_LIBS = @EXTRA_TEST_LIBS@
+F77 = @F77@
+FFLAGS = @FFLAGS@
 GC_CFLAGS = @GC_CFLAGS@
 GC_VERSION = @GC_VERSION@
+GREP = @GREP@
 INCLUDES = @INCLUDES@
 INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
@@ -354,11 +358,9 @@ USE_LIBDIR_TRUE = @USE_LIBDIR_TRUE@
 VERSION = @VERSION@
 WIN32_THREADS_FALSE = @WIN32_THREADS_FALSE@
 WIN32_THREADS_TRUE = @WIN32_THREADS_TRUE@
-ac_ct_AR = @ac_ct_AR@
 ac_ct_CC = @ac_ct_CC@
 ac_ct_CXX = @ac_ct_CXX@
-ac_ct_RANLIB = @ac_ct_RANLIB@
-ac_ct_STRIP = @ac_ct_STRIP@
+ac_ct_F77 = @ac_ct_F77@
 addlibs = @addlibs@
 addobjs = @addobjs@
 am__fastdepCC_FALSE = @am__fastdepCC_FALSE@
@@ -378,23 +380,31 @@ build_cpu = @build_cpu@
 build_os = @build_os@
 build_vendor = @build_vendor@
 datadir = @datadir@
+datarootdir = @datarootdir@
+docdir = @docdir@
+dvidir = @dvidir@
 exec_prefix = @exec_prefix@
+extra_ldflags_libgc = @extra_ldflags_libgc@
 host = @host@
 host_alias = @host_alias@
 host_cpu = @host_cpu@
 host_os = @host_os@
 host_vendor = @host_vendor@
+htmldir = @htmldir@
 includedir = @includedir@
 infodir = @infodir@
 install_sh = @install_sh@
 libdir = @libdir@
 libexecdir = @libexecdir@
+localedir = @localedir@
 localstatedir = @localstatedir@
 mandir = @mandir@
 mkdir_p = @mkdir_p@
 oldincludedir = @oldincludedir@
+pdfdir = @pdfdir@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
+psdir = @psdir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 subdirs = @subdirs@
@@ -558,7 +568,7 @@ libgc_la_SOURCES = allchblk.c alloc.c blacklst.c checksums.c dbg_mlc.c \
 # linuxthread semaphore functions get linked:
 libgc_la_LIBADD = @addobjs@ $(THREADDLLIBS) $(UNWINDLIBS)
 libgc_la_DEPENDENCIES = @addobjs@
-libgc_la_LDFLAGS = -version-info 1:2:0
+libgc_la_LDFLAGS = $(extra_ldflags_libgc) -version-info 1:2:0
 EXTRA_libgc_la_SOURCES = alpha_mach_dep.S \
     mips_sgi_mach_dep.s mips_ultrix_mach_dep.s \
     rs6000_mach_dep.s sparc_mach_dep.S sparc_netbsd_mach_dep.s \

diff --git a/configure b/configure
index bc2fc00c8bf37310c921ea6f7f23406c7fe9f9c7..38c84724450c45d3ecd49a79301d3878eff5c6ba 100755 (executable)
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.ac Revision: 1.19 .
+# From configure.ac Revision: 1.20 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61 for gc 7.0alpha8.
 #
@@ -882,6 +882,7 @@ WIN32_THREADS_TRUE
 WIN32_THREADS_FALSE
 COMPILER_XLC_TRUE
 COMPILER_XLC_FALSE
+extra_ldflags_libgc
 EXTRA_TEST_LIBS
 target_all
 CPLUSPLUS_TRUE
@@ -5997,6 +5998,14 @@ fi
     ;;
 esac
 
+# extra LD Flags which are required for targets
+case "${host}" in
+*-*-darwin*)
+    extra_ldflags_libgc=-Wl,-single_module
+    ;;
+esac
+
+
 
 
 target_all=libgc.la
@@ -6845,7 +6854,7 @@ ia64-*-hpux*)
   ;;
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 6848 "configure"' > conftest.$ac_ext
+  echo '#line 6857 "configure"' > conftest.$ac_ext
   if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
@@ -9108,11 +9117,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:9111: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:9120: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:9115: \$? = $ac_status" >&5
+   echo "$as_me:9124: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -9376,11 +9385,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:9379: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:9388: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:9383: \$? = $ac_status" >&5
+   echo "$as_me:9392: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -9480,11 +9489,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:9483: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:9492: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:9487: \$? = $ac_status" >&5
+   echo "$as_me:9496: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -11788,7 +11797,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 11791 "configure"
+#line 11800 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11888,7 +11897,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 11891 "configure"
+#line 11900 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -14228,11 +14237,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:14231: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:14240: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:14235: \$? = $ac_status" >&5
+   echo "$as_me:14244: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -14332,11 +14341,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:14335: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:14344: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:14339: \$? = $ac_status" >&5
+   echo "$as_me:14348: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -15902,11 +15911,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:15905: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:15914: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:15909: \$? = $ac_status" >&5
+   echo "$as_me:15918: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -16006,11 +16015,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16009: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16018: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:16013: \$? = $ac_status" >&5
+   echo "$as_me:16022: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -18208,11 +18217,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18211: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18220: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:18215: \$? = $ac_status" >&5
+   echo "$as_me:18224: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -18476,11 +18485,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18479: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18488: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:18483: \$? = $ac_status" >&5
+   echo "$as_me:18492: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -18580,11 +18589,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18583: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18592: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:18587: \$? = $ac_status" >&5
+   echo "$as_me:18596: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -22817,6 +22826,7 @@ WIN32_THREADS_TRUE!$WIN32_THREADS_TRUE$ac_delim
 WIN32_THREADS_FALSE!$WIN32_THREADS_FALSE$ac_delim
 COMPILER_XLC_TRUE!$COMPILER_XLC_TRUE$ac_delim
 COMPILER_XLC_FALSE!$COMPILER_XLC_FALSE$ac_delim
+extra_ldflags_libgc!$extra_ldflags_libgc$ac_delim
 EXTRA_TEST_LIBS!$EXTRA_TEST_LIBS$ac_delim
 target_all!$target_all$ac_delim
 CPLUSPLUS_TRUE!$CPLUSPLUS_TRUE$ac_delim
@@ -22850,7 +22860,7 @@ LIBOBJS!$LIBOBJS$ac_delim
 LTLIBOBJS!$LTLIBOBJS$ac_delim
 _ACEOF
 
-  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 46; then
+  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 47; then
     break
   elif $ac_last_try; then
     { { echo "$as_me:$LINENO: error: could not make $CONFIG_STATUS" >&5

diff --git a/configure.ac b/configure.ac
index c4aae485af008f294a0549ce2f9a2421889375c8..f7d98283f5d6758990166e751a01d4c0a88a90c7 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -22,7 +22,7 @@ AC_INIT(gc,7.0alpha8,Hans.Boehm@hp.com)
 AC_CONFIG_SRCDIR(gcj_mlc.c)
 AC_CANONICAL_TARGET 
 AC_PREREQ(2.53)
-AC_REVISION($Revision: 1.20 $)
+AC_REVISION($Revision: 1.21 $)
 GC_SET_VERSION
 AM_INIT_AUTOMAKE([foreign dist-bzip2 subdir-objects nostdinc])
 AM_MAINTAINER_MODE
@@ -293,11 +293,19 @@ fi
 # dyld calls anyway
 case "$host" in
   *-*-darwin*) ;;
-  *) 
+  *)
     AC_CHECK_LIB(dl, dlopen, THREADDLLIBS="$THREADDLLIBS -ldl")
     ;;
 esac
 
+# extra LD Flags which are required for targets
+case "${host}" in
+  *-*-darwin*)
+    extra_ldflags_libgc=-Wl,-single_module
+    ;;
+esac
+AC_SUBST(extra_ldflags_libgc)
+
 AC_SUBST(EXTRA_TEST_LIBS)
 
 target_all=libgc.la

diff --git a/include/private/gcconfig.h b/include/private/gcconfig.h
index d72dde30ac408548b4adc2ae3c4325004864722f..191c99158f33bbf0d092992ed0e590f9784ff941 100644 (file)
--- a/include/private/gcconfig.h
+++ b/include/private/gcconfig.h
@@ -748,25 +748,28 @@
 #     define DATAEND (_end)
 #   endif
 #   ifdef DARWIN
+#     define OS_TYPE "DARWIN"
+#     define DYNAMIC_LOADING
 #     if defined(__ppc64__)
 #       define ALIGNMENT 8
 #       define CPP_WORDSZ 64
+#       define STACKBOTTOM ((ptr_t) 0x7fff5fc00000)
+#       define CACHE_LINE_SIZE 64
+#       ifndef HBLKSIZE
+#         define HBLKSIZE 4096
+#       endif
 #     else
 #       define ALIGNMENT 4
+#       define STACKBOTTOM ((ptr_t) 0xc0000000)
 #     endif
-#     define OS_TYPE "DARWIN"
-#     define DYNAMIC_LOADING
       /* XXX: see get_end(3), get_etext() and get_end() should not be used.
         These aren't used when dyld support is enabled (it is by default) */
 #     define DATASTART ((ptr_t) get_etext())
 #     define DATAEND   ((ptr_t) get_end())
-#     define STACKBOTTOM ((ptr_t) 0xc0000000)
 #     define USE_MMAP
 #     define USE_MMAP_ANON
 #     ifdef GC_DARWIN_THREADS
-       /* This is potentially buggy. It needs more testing. See the comments in
-         os_dep.c.  It relies on threads to track writes. */
-/* #       define MPROTECT_VDB */
+#       define MPROTECT_VDB
 #     endif
 #     include <unistd.h>
 #     define GETPAGESIZE() getpagesize()
@@ -1282,10 +1285,8 @@
 #     define STACKBOTTOM ((ptr_t) 0xc0000000)
 #     define USE_MMAP
 #     define USE_MMAP_ANON
-      /* This is potentially buggy. It needs more testing. See the comments in
-        os_dep.c.  It relies on threads to track writes. */
 #     ifdef GC_DARWIN_THREADS
-/* #       define MPROTECT_VDB -- disabled for now.  May work for some apps. */
+#       define MPROTECT_VDB
 #     endif
 #     include <unistd.h>
 #     define GETPAGESIZE() getpagesize()
@@ -1880,8 +1881,6 @@
 #     define USE_MMAP
 #     define USE_MMAP_ANON
 #     ifdef GC_DARWIN_THREADS
-       /* This is potentially buggy. It needs more testing. See the comments in
-         os_dep.c.  It relies on threads to track writes. */
 #       define MPROTECT_VDB
 #     endif
 #     include <unistd.h>