[PATCH] Link GDBserver with -lmcheck on mainline/development too.

Pedro Alves
2013-06-12T12:21:45Z

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/
2013-06-12 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/
2013-06-12 Pedro Alves <palves@redhat.com>

* Makefile.in (config.status): Depend on development.sh.
* acinclude.m4: Include libmcheck.m4.
* configure: Regenerate.
---
gdb/gdbserver/Makefile.in | 2 +
gdb/gdbserver/acinclude.m4 | 3 ++
gdb/gdbserver/configure | 70 ++++++++++++++++++++++++++++++++++++++++++++
gdb/gdbserver/configure.ac | 12 ++++++++
4 files changed, 86 insertions(+), 1 deletion(-)

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index a6336a2..9cd838d 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -1347,7 +1347,7 @@ 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
@@ -1357,6 +1357,7 @@ ACLOCAL_AMFLAGS = -I ../config
aclocal_m4_deps = \
configure.ac \
acx_configure_dir.m4 \
+ libmcheck.m4 \
../bfd/bfd.m4 \
../config/acinclude.m4 \
../config/plugins.m4 \
diff --git a/gdb/acinclude.m4 b/gdb/acinclude.m4
index df7d8c0..a05eb4d 100644
--- a/gdb/acinclude.m4
+++ b/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)

diff --git a/gdb/configure b/gdb/configure
index 383d634..f3d74ae 100755
--- a/gdb/configure
+++ b/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 it to 'true' for development snapshots, 'false' for releases or
-# pre-releases.
-development=true
+# Set the 'development' global.
+. $srcdir/development.sh

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}" \
- -a \( "${have_libpython}" = "no" \
- -o "${python_has_threads}" = "no" \) \
- && $development; then
- ENABLE_LIBMCHECK=yes
+if test \( "${have_libpython}" = "no" -o "${python_has_threads}" = "no" \) \
+ && $development; then
+ libmcheck_default=yes
+else
+ libmcheck_default=no
fi

-if test "$ENABLE_LIBMCHECK" = "yes" ; then
- if test "${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;}
+ # 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
- { $as_echo "$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

# ------------------------- #
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 46a97bd..db92df0 100644
--- a/gdb/configure.ac
+++ b/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 it to 'true' for development snapshots, 'false' for releases or
-# pre-releases.
-development=true
+# Set the 'development' global.
+. $srcdir/development.sh

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}" \
- -a \( "${have_libpython}" = "no" \
- -o "${python_has_threads}" = "no" \) \
- && $development; then
- ENABLE_LIBMCHECK=yes
+if test \( "${have_libpython}" = "no" -o "${python_has_threads}" = "no" \) \
+ && $development; then
+ libmcheck_default=yes
+else
+ libmcheck_default=no
fi
+GDB_AC_LIBMCHECK(${libmcheck_default})

-if test "$ENABLE_LIBMCHECK" = "yes" ; then
- if test "${have_libpython}" != "no" -a "${python_has_threads}" = "yes" ; then
- AC_MSG_WARN(--enable-libmcheck may lead to spurious crashes if threads are used in python)
- fi
- AC_CHECK_LIB(mcheck, main)
+if test "$ENABLE_LIBMCHECK" = "yes" \
+ -a "${have_libpython}" != "no" \
+ -a "${python_has_threads}" = "yes" ; then
+ AC_MSG_WARN(--enable-libmcheck may lead to spurious crashes if threads are used in python)
fi

# ------------------------- #
diff --git a/gdb/development.sh b/gdb/development.sh
new file mode 100644
index 0000000..90435ca
--- /dev/null
+++ b/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
diff --git a/gdb/gdbserver/Makefile.in b/gdb/gdbserver/Makefile.in
index e8470a8..485ad43 100644
--- a/gdb/gdbserver/Makefile.in
+++ b/gdb/gdbserver/Makefile.in
@@ -377,7 +377,7 @@ $(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
diff --git a/gdb/gdbserver/acinclude.m4 b/gdb/gdbserver/acinclude.m4
index 0e0bdc8..4008d96 100644
--- a/gdb/gdbserver/acinclude.m4
+++ b/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)

diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index b87fedb..5d78d33 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -685,6 +685,7 @@ ac_user_opts='
enable_option_checking
enable_maintainer_mode
enable_largefile
+enable_libmcheck
with_ust
with_ust_include
with_ust_lib
@@ -1324,6 +1325,7 @@ 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
@@ -4478,6 +4480,74 @@ _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
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index b9928d7..d29d59a 100644
--- a/gdb/gdbserver/configure.ac
+++ b/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])
diff --git a/gdb/libmcheck.m4 b/gdb/libmcheck.m4
new file mode 100644
index 0000000..7493147
--- /dev/null
+++ b/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
+])