[v2,10/10] Add --enable-ubsan
Commit Message
This adds --enable-ubsan to gdb's configure. By default it is enabled
in development mode, and disabled otherwise. This passes both
-fsanitize=undefined and -fno-sanitize-recover=undefined to
compilations, so that undefined behavior violations will be sure to
cause test failures.
gdb/ChangeLog
2018-10-01 Tom Tromey <tom@tromey.com>
* README: Mention --enable-ubsan.
* NEWS: Mention --enable-ubsan.
* acinclude.m4: Include sanitize.m4.
* configure: Rebuild.
* configure.ac: Call AM_GDB_UBSAN.
* sanitize.m4: New file.
gdb/doc/ChangeLog
2018-10-01 Tom Tromey <tom@tromey.com>
* gdb.texinfo (Configure Options): Document --enable-ubsan.
---
gdb/ChangeLog | 9 ++++
gdb/NEWS | 8 ++++
gdb/README | 7 +++
gdb/acinclude.m4 | 3 ++
gdb/configure | 105 ++++++++++++++++++++++++++++++++++++++++++++
gdb/configure.ac | 1 +
gdb/doc/ChangeLog | 4 ++
gdb/doc/gdb.texinfo | 7 +++
gdb/sanitize.m4 | 46 +++++++++++++++++++
9 files changed, 190 insertions(+)
create mode 100644 gdb/sanitize.m4
Comments
> From: Tom Tromey <tom@tromey.com>
> Cc: Tom Tromey <tom@tromey.com>
> Date: Mon, 1 Oct 2018 22:44:20 -0600
>
> --- a/gdb/NEWS
> +++ b/gdb/NEWS
> @@ -103,6 +103,14 @@ CSKY GNU/LINUX csky*-*-linux
> ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
> of objfiles associated to that program space.
>
> +* Configure changes
> +
> +--enable-ubsan
> +
> + Enable or disable the undefined behavior sanitizer. Release
> + versions of gdb disable this by default, but development versions
"GDB", capitalized, I guess?
> --- a/gdb/README
> +++ b/gdb/README
> @@ -538,6 +538,13 @@ more obscure GDB `configure' options are not listed here.
> the compiler, which will fail the compilation if the compiler
> outputs any warning messages.
>
> +`--enable-ubsan'
> + Enable the GCC undefined behavior sanitizer. By default this is
> + disabled in GDB releases, but enabled when building from git.
> + The undefined behavior sanitizer checks for C++ undefined
> + behavior. It has a performance cost, so if you are looking at
> + GDB's performance, you should disable it.
Does this require some minimal version of g++? If so, I think we
should mention that. And what about testing for this support at
configure time?
> +
> +# ac_fn_cxx_try_link LINENO
> +# -------------------------
> +# Try to link conftest.$ac_ext, and return whether this succeeded.
> +ac_fn_cxx_try_link ()
> +{
> + as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
> + rm -f conftest.$ac_objext conftest$ac_exeext
> + if { { ac_try="$ac_link"
> +case "(($ac_try" in
> + *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
> + *) ac_try_echo=$ac_try;;
> +esac
> +eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
> +$as_echo "$ac_try_echo"; } >&5
> + (eval "$ac_link") 2>conftest.err
> + ac_status=$?
> + if test -s conftest.err; then
> + grep -v '^ *+' conftest.err >conftest.er1
> + cat conftest.er1 >&5
> + mv -f conftest.er1 conftest.err
> + fi
> + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
> + test $ac_status = 0; } && {
> + test -z "$ac_cxx_werror_flag" ||
> + test ! -s conftest.err
> + } && test -s conftest$ac_exeext && {
> + test "$cross_compiling" = yes ||
> + test -x conftest$ac_exeext
> + }; then :
> + ac_retval=0
> +else
> + $as_echo "$as_me: failed program was:" >&5
> +sed 's/^/| /' conftest.$ac_ext >&5
> +
> + ac_retval=1
> +fi
> + # Delete the IPA/IPO (Inter Procedural Analysis/Optimization) information
> + # created by the PGI compiler (conftest_ipa8_conftest.oo), as it would
> + # interfere with the next link command; also delete a directory that is
> + # left behind by Apple's compiler. We do this before executing the actions.
> + rm -rf conftest.dSYM conftest_ipa8_conftest.oo
> + eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
> + as_fn_set_status $ac_retval
> +
> +} # ac_fn_cxx_try_link
> cat >config.log <<_ACEOF
> This file contains any messages produced by compilers while
> running configure, to aid debugging if configure makes a mistake.
Is this hunk related to the issue at hand?
The documentation parts are approved, with the above nits fixed.
Thanks.
>>>>> "Eli" == Eli Zaretskii <eliz@gnu.org> writes:
>> + Enable or disable the undefined behavior sanitizer. Release
>> + versions of gdb disable this by default, but development versions
Eli> "GDB", capitalized, I guess?
Done.
>> +`--enable-ubsan'
>> + Enable the GCC undefined behavior sanitizer. By default this is
>> + disabled in GDB releases, but enabled when building from git.
>> + The undefined behavior sanitizer checks for C++ undefined
>> + behavior. It has a performance cost, so if you are looking at
>> + GDB's performance, you should disable it.
Eli> Does this require some minimal version of g++? If so, I think we
Eli> should mention that. And what about testing for this support at
Eli> configure time?
It was in GCC 4.9. It is tested at configure time. I've updated the
text & will send a new patch.
>> +# ac_fn_cxx_try_link LINENO
>> +# -------------------------
[..]
Eli> Is this hunk related to the issue at hand?
Yes, I think it's part of configure expansion of the new test.
Tom
On 10/02/2018 05:44 AM, Tom Tromey wrote:
> This adds --enable-ubsan to gdb's configure. By default it is enabled
> in development mode, and disabled otherwise. This passes both
> -fsanitize=undefined and -fno-sanitize-recover=undefined to
> compilations, so that undefined behavior violations will be sure to
> cause test failures.
Thanks much for all the docs additions, and all the preparatory
work that came with it.
> --- /dev/null
> +++ b/gdb/sanitize.m4
> @@ -0,0 +1,46 @@
> +dnl Autoconf configure script for GDB, the GNU debugger.
Nit: I guess this was copied from warning.m4, but, could you
tweak this intro comment, which seems to have been originally
blindly copied from configure.ac into warning.m4?
Otherwise LGTM.
Thanks,
Pedro Alves
>>>>> "Pedro" == Pedro Alves <palves@redhat.com> writes:
>> --- /dev/null
>> +++ b/gdb/sanitize.m4
>> @@ -0,0 +1,46 @@
>> +dnl Autoconf configure script for GDB, the GNU debugger.
Pedro> Nit: I guess this was copied from warning.m4, but, could you
Pedro> tweak this intro comment, which seems to have been originally
Pedro> blindly copied from configure.ac into warning.m4?
I've tweaked it.
Tom
@@ -103,6 +103,14 @@ CSKY GNU/LINUX csky*-*-linux
** The gdb.Progspace type has a new 'objfiles' method, which returns the list
of objfiles associated to that program space.
+* Configure changes
+
+--enable-ubsan
+
+ Enable or disable the undefined behavior sanitizer. Release
+ versions of gdb disable this by default, but development versions
+ enable it. Enabling this can cause a performance penalty.
+
*** Changes in GDB 8.2
* The 'set disassembler-options' command now supports specifying options
@@ -538,6 +538,13 @@ more obscure GDB `configure' options are not listed here.
the compiler, which will fail the compilation if the compiler
outputs any warning messages.
+`--enable-ubsan'
+ Enable the GCC undefined behavior sanitizer. By default this is
+ disabled in GDB releases, but enabled when building from git.
+ The undefined behavior sanitizer checks for C++ undefined
+ behavior. It has a performance cost, so if you are looking at
+ GDB's performance, you should disable it.
+
`configure' accepts other options, for compatibility with configuring
other GNU tools recursively.
@@ -15,6 +15,9 @@ sinclude(transform.m4)
# This gets AM_GDB_WARNINGS.
sinclude(warning.m4)
+# AM_GDB_UBSAN
+sinclude(sanitize.m4)
+
dnl gdb/configure.in uses BFD_NEED_DECLARATION, so get its definition.
sinclude(../bfd/bfd.m4)
@@ -886,6 +886,7 @@ with_system_gdbinit
enable_werror
enable_build_warnings
enable_gdb_build_warnings
+enable_ubsan
with_lzma
with_liblzma_prefix
with_tcl
@@ -1556,6 +1557,7 @@ Optional Features:
--enable-gdb-build-warnings
enable GDB specific build-time compiler warnings if
gcc is used
+ --enable-ubsan enable undefined behavior sanitizer (auto/yes/no)
--enable-sim link gdb with simulator
--enable-gdbserver automatically build gdbserver (yes/no/auto, default
is auto)
@@ -2448,6 +2450,52 @@ $as_echo "$ac_res" >&6; }
eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
} # ac_fn_c_check_decl
+
+# ac_fn_cxx_try_link LINENO
+# -------------------------
+# Try to link conftest.$ac_ext, and return whether this succeeded.
+ac_fn_cxx_try_link ()
+{
+ as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
+ rm -f conftest.$ac_objext conftest$ac_exeext
+ if { { ac_try="$ac_link"
+case "(($ac_try" in
+ *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+ *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
+$as_echo "$ac_try_echo"; } >&5
+ (eval "$ac_link") 2>conftest.err
+ ac_status=$?
+ if test -s conftest.err; then
+ grep -v '^ *+' conftest.err >conftest.er1
+ cat conftest.er1 >&5
+ mv -f conftest.er1 conftest.err
+ fi
+ $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+ test $ac_status = 0; } && {
+ test -z "$ac_cxx_werror_flag" ||
+ test ! -s conftest.err
+ } && test -s conftest$ac_exeext && {
+ test "$cross_compiling" = yes ||
+ test -x conftest$ac_exeext
+ }; then :
+ ac_retval=0
+else
+ $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ ac_retval=1
+fi
+ # Delete the IPA/IPO (Inter Procedural Analysis/Optimization) information
+ # created by the PGI compiler (conftest_ipa8_conftest.oo), as it would
+ # interfere with the next link command; also delete a directory that is
+ # left behind by Apple's compiler. We do this before executing the actions.
+ rm -rf conftest.dSYM conftest_ipa8_conftest.oo
+ eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
+ as_fn_set_status $ac_retval
+
+} # ac_fn_cxx_try_link
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.
@@ -15561,6 +15609,63 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
+# Check whether --enable-ubsan was given.
+if test "${enable_ubsan+set}" = set; then :
+ enableval=$enable_ubsan;
+else
+ enable_ubsan=auto
+fi
+
+if test "x$enable_ubsan" = xauto; then
+ if $development; then
+ enable_ubsan=yes
+ fi
+fi
+ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+if test "x$enable_ubsan" = xyes; then
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -fsanitize=undefined is accepted" >&5
+$as_echo_n "checking whether -fsanitize=undefined is accepted... " >&6; }
+ saved_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS -fsanitize=undefined -fno-sanitize-recover=undefined"
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+int
+main ()
+{
+
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_link "$LINENO"; then :
+ enable_ubsan=yes
+else
+ enable_ubsan=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+ CXXFLAGS="$saved_CXXFLAGS"
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_ubsan" >&5
+$as_echo "$enable_ubsan" >&6; }
+ if test "x$enable_ubsan" = xyes; then
+ WARN_CFLAGS="$WARN_CFLAGS -fsanitize=undefined -fno-sanitize-recover=undefined"
+ CONFIG_LDFLAGS="$CONFIG_LDFLAGS -fsanitize=undefined"
+ fi
+fi
+ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+
# In the Cygwin environment, we need some additional flags.
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for cygwin" >&5
$as_echo_n "checking for cygwin... " >&6; }
@@ -1838,6 +1838,7 @@ GDB_AC_WITH_DIR(SYSTEM_GDBINIT, system-gdbinit,
[])
AM_GDB_WARNINGS
+AM_GDB_UBSAN
# In the Cygwin environment, we need some additional flags.
AC_CACHE_CHECK([for cygwin], gdb_cv_os_cygwin,
@@ -35744,6 +35744,13 @@ compiler you are using.
Treat compiler warnings as werrors. It adds the @code{-Werror} flag
to the compiler, which will fail the compilation if the compiler
outputs any warning messages.
+
+@item --enable-ubsan
+Enable the GCC undefined behavior sanitizer. By default this is
+disabled in @value{GDBN} releases, but enabled when building from git.
+The undefined behavior sanitizer checks for C@t{++} undefined
+behavior. It has a performance cost, so if you are looking at
+@value{GDBN}'s performance, you should disable it.
@end table
@node System-wide configuration
new file mode 100644
@@ -0,0 +1,46 @@
+dnl Autoconf configure script for GDB, the GNU debugger.
+dnl Copyright (C) 2018 Free Software Foundation, Inc.
+dnl
+dnl This file is part of GDB.
+dnl
+dnl This program is free software; you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 3 of the License, or
+dnl (at your option) any later version.
+dnl
+dnl This program is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+dnl GNU General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU General Public License
+dnl along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+AC_DEFUN([AM_GDB_UBSAN],[
+AC_ARG_ENABLE(ubsan,
+ AS_HELP_STRING([--enable-ubsan],
+ [enable undefined behavior sanitizer (auto/yes/no)]),
+ [],enable_ubsan=auto)
+if test "x$enable_ubsan" = xauto; then
+ if $development; then
+ enable_ubsan=yes
+ fi
+fi
+AC_LANG_PUSH([C++])
+if test "x$enable_ubsan" = xyes; then
+ AC_MSG_CHECKING(whether -fsanitize=undefined is accepted)
+ saved_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS -fsanitize=undefined -fno-sanitize-recover=undefined"
+ dnl A link check is required because it is possible to install gcc
+ dnl without libubsan, leading to link failures when compiling with
+ dnl -fsanitize=undefined.
+ AC_TRY_LINK([],[],enable_ubsan=yes,enable_ubsan=no)
+ CXXFLAGS="$saved_CXXFLAGS"
+ AC_MSG_RESULT($enable_ubsan)
+ if test "x$enable_ubsan" = xyes; then
+ WARN_CFLAGS="$WARN_CFLAGS -fsanitize=undefined -fno-sanitize-recover=undefined"
+ CONFIG_LDFLAGS="$CONFIG_LDFLAGS -fsanitize=undefined"
+ fi
+fi
+AC_LANG_POP([C++])
+])