On mainline/development, also link GDBserver with -lmcheck.

This factors --enable-libmcheck related bits from GDB's configure.ac
and makes GDBserver use them too.  Specifically, the 'development'
global is moved to a separate script to it can be sourced by both GDB
and GDBserver, and the --enable-libmcheck/--disable-libmcheck bits
proper are moved to a new m4 file.

I started out by defining 'development' in the m4 file, but in the end
decided against it, as a separate script has the advantage that
changing it in release branches does not require regenerating
configure, unlike today.

I had also started out by making the new GDB_AC_LIBMCHECK itself
handle the yes/no default fallback depending on release/developement,
but since I had split out 'development' to a separate script, and, GDB
needs the python checks anyway (hence we'd need to do the python
checks in gdb's configure.ac, and pass in a 'default lmcheck yes/no'
parameter to GDB_AC_LIBMCHECK anyway), I ended up keeping
GDB_AC_LIBMCHECK isolated from the 'development' global.  IOW, it's
the caller's business to handle it.

Tested on x86_64 Fedora 17.  Built GDB and GDBserver with and without
--enable-libmcheck, and observed --enable-libmcheck overrides the
disablement of -lmcheck caused by python supporting threads, and that
GDBserver links with -lmcheck when expected.  Also observed that
changing the 'development' global, and issuing "make" triggers a
relink, and '-lmcheck' is included or not from the link accordingly.

gdb/
2013-07-03  Pedro Alves  <palves@redhat.com>

	* Makefile.in (config.status): Depend on development.sh.
	(aclocal_m4_deps): Add libmcheck.m4.
	* acinclude.m4: Include libmcheck.m4.
	* configure.ac: Source development.sh instead of setting
	'development' here.  --enable-libmcheck/--disable-libmcheck code
	factored out to GDB_AC_LIBMCHECK.  Run it.
	* development.sh: New file.
	* libmcheck.m4: New file.
	* configure: Regenerate.

gdb/gdbserver/
2013-07-03  Pedro Alves  <palves@redhat.com>

	* Makefile.in (config.status): Depend on development.sh.
	* acinclude.m4: Include libmcheck.m4.
	* configure: Regenerate.

gdb/ChangeLog

@@ -1,3 +1,15 @@
+2013-07-03  Pedro Alves  <palves@redhat.com>
+
+	* Makefile.in (config.status): Depend on development.sh.
+	(aclocal_m4_deps): Add libmcheck.m4.
+	* acinclude.m4: Include libmcheck.m4.
+	* configure.ac: Source development.sh instead of setting
+	'development' here.  --enable-libmcheck/--disable-libmcheck code
+	factored out to GDB_AC_LIBMCHECK.  Run it.
+	* development.sh: New file.
+	* libmcheck.m4: New file.
+	* configure: Regenerate.
+
 2013-07-02  Tom Tromey  <tromey@redhat.com>
 
 	* contrib/ari/update-web-ari.sh: Update for version.in change.

gdb/Makefile.in

@@ -1348,7 +1348,7 @@ stamp-h: $(srcdir)/config.in config.status
 	  CONFIG_LINKS= \
 	  $(SHELL) config.status
 
-config.status: $(srcdir)/configure configure.tgt configure.host
+config.status: $(srcdir)/configure configure.tgt configure.host development.sh
 	$(SHELL) config.status --recheck
 
 ACLOCAL = aclocal
@@ -1358,6 +1358,7 @@ ACLOCAL_AMFLAGS = -I ../config
 aclocal_m4_deps = \
 	configure.ac \
 	acx_configure_dir.m4 \
+	libmcheck.m4 \
 	../bfd/bfd.m4 \
 	../config/acinclude.m4 \
 	../config/plugins.m4 \

gdb/acinclude.m4

@@ -6,6 +6,9 @@ dnl major rewriting for Tcl 7.5 by Don Libes <libes@nist.gov>
 
 sinclude(acx_configure_dir.m4)
 
+# This gets GDB_AC_LIBMCHECK.
+sinclude(libmcheck.m4)
+
 dnl gdb/configure.in uses BFD_NEED_DECLARATION, so get its definition.
 sinclude(../bfd/bfd.m4)
 

gdb/configure

@@ -1480,7 +1480,7 @@ Optional Features:
   --enable-gdbtk          enable gdbtk graphical user interface (GUI)
   --enable-profiling      enable profiling of GDB
   --disable-rpath         do not hardcode runtime library paths
-  --enable-libmcheck      Try building GDB with -lmcheck if available
+  --enable-libmcheck      Try linking with -lmcheck if available
   --enable-werror         treat compile warnings as errors
   --enable-build-warnings enable build-time compiler warnings if gcc is used
   --enable-gdb-build-warnings
@@ -2704,10 +2704,8 @@ fi
 
 
 
-# Provide more thorough testing by -lmcheck.
+# Set the 'development' global.
-# Set it to 'true' for development snapshots, 'false' for releases or
+. $srcdir/development.sh
-# pre-releases.
-development=true
 
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
@@ -8565,36 +8563,33 @@ fi
 
 
 
-# Provide a --enable-libmcheck/--disable-libmcheck set of options
-# allowing a user to enable this option even when building releases,
-# or to disable it when building a snapshot.
-# Check whether --enable-libmcheck was given.
-if test "${enable_libmcheck+set}" = set; then :
-  enableval=$enable_libmcheck; case "${enableval}" in
-     yes | y) ENABLE_LIBMCHECK="yes" ;;
-     no | n)  ENABLE_LIBMCHECK="no" ;;
-     *) as_fn_error "bad value ${enableval} for --enable-libmcheck" "$LINENO" 5 ;;
-   esac
-fi
-
-
 # Enable -lmcheck by default (it provides cheap-enough memory mangling),
 # but turn it off if Python is enabled with threads, since -lmcheck is
 # not thread safe (http://sourceware.org/bugzilla/show_bug.cgi?id=9939),
 # and for releases.
-if test -z "${ENABLE_LIBMCHECK}" \
+if test \( "${have_libpython}" = "no" -o "${python_has_threads}" = "no" \) \
-        -a \( "${have_libpython}" = "no" \
+   && $development; then
-	     -o "${python_has_threads}" = "no" \) \
+  libmcheck_default=yes
-    && $development; then
+else
-  ENABLE_LIBMCHECK=yes
+  libmcheck_default=no
 fi
 
-if test "$ENABLE_LIBMCHECK" = "yes" ; then
+  # Check whether --enable-libmcheck was given.
-  if test "${have_libpython}" != "no" -a "${python_has_threads}" = "yes" ; then
+if test "${enable_libmcheck+set}" = set; then :
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-libmcheck may lead to spurious crashes if threads are used in python" >&5
+  enableval=$enable_libmcheck; case "${enableval}" in
-$as_echo "$as_me: WARNING: --enable-libmcheck may lead to spurious crashes if threads are used in python" >&2;}
+      yes | y) ENABLE_LIBMCHECK="yes" ;;
+      no | n)  ENABLE_LIBMCHECK="no" ;;
+      *) as_fn_error "bad value ${enableval} for --enable-libmcheck" "$LINENO" 5 ;;
+    esac
+fi
+
+
+  if test -z "${ENABLE_LIBMCHECK}"; then
+    ENABLE_LIBMCHECK=${libmcheck_default}
   fi
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for main in -lmcheck" >&5
+
+  if test "$ENABLE_LIBMCHECK" = "yes" ; then
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for main in -lmcheck" >&5
 $as_echo_n "checking for main in -lmcheck... " >&6; }
 if test "${ac_cv_lib_mcheck_main+set}" = set; then :
   $as_echo_n "(cached) " >&6
@@ -8633,6 +8628,14 @@ _ACEOF
 
 fi
 
+  fi
+
+
+if test "$ENABLE_LIBMCHECK" = "yes" \
+	-a "${have_libpython}" != "no" \
+	-a "${python_has_threads}" = "yes" ; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-libmcheck may lead to spurious crashes if threads are used in python" >&5
+$as_echo "$as_me: WARNING: --enable-libmcheck may lead to spurious crashes if threads are used in python" >&2;}
 fi
 
 # ------------------------- #

gdb/configure.ac

@@ -23,10 +23,8 @@ AC_INIT(main.c)
 AC_CONFIG_HEADER(config.h:config.in)
 AM_MAINTAINER_MODE
 
-# Provide more thorough testing by -lmcheck.
+# Set the 'development' global.
-# Set it to 'true' for development snapshots, 'false' for releases or
+. $srcdir/development.sh
-# pre-releases.
-development=true
 
 AC_PROG_CC
 AC_USE_SYSTEM_EXTENSIONS
@@ -1052,34 +1050,22 @@ AC_SUBST(PYTHON_CFLAGS)
 AC_SUBST(PYTHON_CPPFLAGS)
 AC_SUBST(PYTHON_LIBS)
 
-# Provide a --enable-libmcheck/--disable-libmcheck set of options
-# allowing a user to enable this option even when building releases,
-# or to disable it when building a snapshot.
-AC_ARG_ENABLE(libmcheck,
-  AS_HELP_STRING([--enable-libmcheck],
-                 [Try building GDB with -lmcheck if available]),
-  [case "${enableval}" in
-     yes | y) ENABLE_LIBMCHECK="yes" ;;
-     no | n)  ENABLE_LIBMCHECK="no" ;;
-     *) AC_MSG_ERROR(bad value ${enableval} for --enable-libmcheck) ;;
-   esac])
-
 # Enable -lmcheck by default (it provides cheap-enough memory mangling),
 # but turn it off if Python is enabled with threads, since -lmcheck is
 # not thread safe (http://sourceware.org/bugzilla/show_bug.cgi?id=9939),
 # and for releases.
-if test -z "${ENABLE_LIBMCHECK}" \
+if test \( "${have_libpython}" = "no" -o "${python_has_threads}" = "no" \) \
-        -a \( "${have_libpython}" = "no" \
+   && $development; then
-	     -o "${python_has_threads}" = "no" \) \
+  libmcheck_default=yes
-    && $development; then
+else
-  ENABLE_LIBMCHECK=yes
+  libmcheck_default=no
 fi
+GDB_AC_LIBMCHECK(${libmcheck_default})
 
-if test "$ENABLE_LIBMCHECK" = "yes" ; then
+if test "$ENABLE_LIBMCHECK" = "yes" \
-  if test "${have_libpython}" != "no" -a "${python_has_threads}" = "yes" ; then
+	-a "${have_libpython}" != "no" \
-    AC_MSG_WARN(--enable-libmcheck may lead to spurious crashes if threads are used in python)
+	-a "${python_has_threads}" = "yes" ; then
-  fi
+  AC_MSG_WARN(--enable-libmcheck may lead to spurious crashes if threads are used in python)
-  AC_CHECK_LIB(mcheck, main)
 fi
 
 # ------------------------- #

gdb/development.sh

@@ -0,0 +1,21 @@
+# Copyright (C) 2012-2013 Free Software Foundation, Inc.
+#
+# This file is part of GDB.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Set to 'true' for development snapshots, 'false' for releases and
+# pre-releases.  When true, provide more thorough testing with
+# -lmcheck.
+development=true

gdb/gdbserver/ChangeLog

@@ -1,3 +1,9 @@
+2013-07-03  Pedro Alves  <palves@redhat.com>
+
+	* Makefile.in (config.status): Depend on development.sh.
+	* acinclude.m4: Include libmcheck.m4.
+	* configure: Regenerate.
+
 2013-07-02  Mircea Gherzan  <mircea.gherzan@intel.com>
 
 	* win32-low.c (winapi_DebugActiveProcessStop): Move the WINAPI

gdb/gdbserver/Makefile.in

@@ -379,7 +379,7 @@ $(GNULIB_BUILDDIR)/Makefile: $(srcdir)/../gnulib/Makefile.in config.status
 	  CONFIG_LINKS= \
 	  $(SHELL) config.status
 
-config.status: configure configure.srv
+config.status: configure configure.srv $(srcdir)/../development.sh
 	$(SHELL) ./config.status --recheck
 
 # automatic rebuilding in automake-generated Makefiles requires

gdb/gdbserver/acinclude.m4

@@ -3,6 +3,9 @@ sinclude(../../bfd/bfd.m4)
 
 sinclude(../acx_configure_dir.m4)
 
+# This gets GDB_AC_LIBMCHECK.
+sinclude(../libmcheck.m4)
+
 dnl This gets autoconf bugfixes
 sinclude(../../config/override.m4)
 

gdb/gdbserver/configure

@@ -687,6 +687,7 @@ ac_user_opts='
 enable_option_checking
 enable_maintainer_mode
 enable_largefile
+enable_libmcheck
 with_ust
 with_ust_include
 with_ust_lib
@@ -1326,6 +1327,7 @@ Optional Features:
   --enable-maintainer-mode  enable make rules and dependencies not useful
 			  (and sometimes confusing) to the casual installer
   --disable-largefile     omit support for large files
+  --enable-libmcheck      Try linking with -lmcheck if available
   --enable-werror         treat compile warnings as errors
   --enable-inprocess-agent
                           inprocess agent
@@ -4480,6 +4482,74 @@ _ACEOF
 fi
 
 
+# Set the 'development' global.
+. $srcdir/../development.sh
+
+# Enable -lmcheck by default (it provides cheap-enough memory
+# mangling), but turn it off for releases.
+if $development; then
+  libmcheck_default=yes
+else
+  libmcheck_default=no
+fi
+
+  # Check whether --enable-libmcheck was given.
+if test "${enable_libmcheck+set}" = set; then :
+  enableval=$enable_libmcheck; case "${enableval}" in
+      yes | y) ENABLE_LIBMCHECK="yes" ;;
+      no | n)  ENABLE_LIBMCHECK="no" ;;
+      *) as_fn_error "bad value ${enableval} for --enable-libmcheck" "$LINENO" 5 ;;
+    esac
+fi
+
+
+  if test -z "${ENABLE_LIBMCHECK}"; then
+    ENABLE_LIBMCHECK=${libmcheck_default}
+  fi
+
+  if test "$ENABLE_LIBMCHECK" = "yes" ; then
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for main in -lmcheck" >&5
+$as_echo_n "checking for main in -lmcheck... " >&6; }
+if test "${ac_cv_lib_mcheck_main+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lmcheck  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+
+int
+main ()
+{
+return main ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_mcheck_main=yes
+else
+  ac_cv_lib_mcheck_main=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_mcheck_main" >&5
+$as_echo "$ac_cv_lib_mcheck_main" >&6; }
+if test "x$ac_cv_lib_mcheck_main" = x""yes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBMCHECK 1
+_ACEOF
+
+  LIBS="-lmcheck $LIBS"
+
+fi
+
+  fi
+
+
 # Dependency checking.
 rm -rf .tst 2>/dev/null
 mkdir .tst 2>/dev/null

gdb/gdbserver/configure.ac

@@ -41,6 +41,18 @@ AC_HEADER_DIRENT
 
 AC_FUNC_ALLOCA
 
+# Set the 'development' global.
+. $srcdir/../development.sh
+
+# Enable -lmcheck by default (it provides cheap-enough memory
+# mangling), but turn it off for releases.
+if $development; then
+  libmcheck_default=yes
+else
+  libmcheck_default=no
+fi
+GDB_AC_LIBMCHECK(${libmcheck_default})
+
 # Dependency checking.
 ZW_CREATE_DEPDIR
 ZW_PROG_COMPILER_DEPENDENCIES([CC])

gdb/libmcheck.m4

@@ -0,0 +1,43 @@
+dnl Copyright (C) 2012-2013 Free Software Foundation, Inc.
+dnl
+dnl This file is part of GDB.
+dnl
+dnl This program is free software; you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 3 of the License, or
+dnl (at your option) any later version.
+dnl
+dnl This program is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+dnl GNU General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU General Public License
+dnl along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+dnl GDB_AC_LIBMCHECK([DEFAULT])
+dnl Provide an --enable-libmcheck/--disable-libmcheck set of options
+dnl allowing a user to enable this option even when building releases,
+dnl or to disable it when building a snapshot.
+dnl DEFAULT (yes/no) is used as default if the user doesn't set
+dnl the option explicitly.
+
+AC_DEFUN([GDB_AC_LIBMCHECK],
+[
+  AC_ARG_ENABLE(libmcheck,
+    AS_HELP_STRING([--enable-libmcheck],
+		   [Try linking with -lmcheck if available]),
+    [case "${enableval}" in
+      yes | y) ENABLE_LIBMCHECK="yes" ;;
+      no | n)  ENABLE_LIBMCHECK="no" ;;
+      *) AC_MSG_ERROR(bad value ${enableval} for --enable-libmcheck) ;;
+    esac])
+
+  if test -z "${ENABLE_LIBMCHECK}"; then
+    ENABLE_LIBMCHECK=[$1]
+  fi
+
+  if test "$ENABLE_LIBMCHECK" = "yes" ; then
+    AC_CHECK_LIB(mcheck, main)
+  fi
+])