Use -Wabi=2 to fix warnings about -Wabi having no effect on its own.
This requires suppressing two warnings in src/c++11/debug.cc which do
not affect the library ABI.
Previously libstdc++ defaulted to --enable-werror but the -Werror flag
was not actually added unless --enable-maintainer-mode was used. This is
not documented and not the expected behaviour. This removes any special
treatment for maintainer-mode, makes -Werror depend directly on
--enable-werror, and changes the default to --enable-werror=no.
PR libstdc++/86450
* acinclude.m4 (GLIBCXX_CHECK_COMPILER_FEATURES): Don't define WERROR.
(GLIBCXX_EXPORT_FLAGS): Use -Wabi=2 instead of -Wabi.
* configure: Regenerate.
* configure.ac: Change GLIBCXX_ENABLE_WERROR default to "no".
* doc/Makefile.in: Regenerate.
* fragment.am: Set WERROR_FLAG to -Werror instead of $(WERROR).
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++11/debug.cc: Use diagnostic pragmas to suppress warnings
from -Wabi=2 that don't affect exported symbols.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
Tested powerpc64le-linux, committed to trunk.
commit 0e99fd82ce20499c4da0d0950e7197f14d45311f
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Tue Jul 17 00:59:17 2018 +0100
PR libstdc++/86450 use -Wabi=2 and simplify -Werror use
Use -Wabi=2 to fix warnings about -Wabi having no effect on its own.
This requires suppressing two warnings in src/c++11/debug.cc which do
not affect the library ABI.
Previously libstdc++ defaulted to --enable-werror but the -Werror flag
was not actually added unless --enable-maintainer-mode was used. This is
not documented and not the expected behaviour. This removes any special
treatment for maintainer-mode, makes -Werror depend directly on
--enable-werror, and changes the default to --enable-werror=no.
PR libstdc++/86450
* acinclude.m4 (GLIBCXX_CHECK_COMPILER_FEATURES): Don't define
WERROR.
(GLIBCXX_EXPORT_FLAGS): Use -Wabi=2 instead of -Wabi.
* configure: Regenerate.
* configure.ac: Change GLIBCXX_ENABLE_WERROR default to "no".
* doc/Makefile.in: Regenerate.
* fragment.am: Set WERROR_FLAG to -Werror instead of $(WERROR).
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++11/debug.cc: Use diagnostic pragmas to suppress warnings
from -Wabi=2 that don't affect exported symbols.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index cf5add167e6..bbf3c8df3e1 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -140,13 +140,6 @@ AC_DEFUN([GLIBCXX_CHECK_COMPILER_FEATURES], [
ac_test_CXXFLAGS="${CXXFLAGS+set}"
ac_save_CXXFLAGS="$CXXFLAGS"
- # Check for maintainer-mode bits.
- if test x"$USE_MAINTAINER_MODE" = xno; then
- WERROR=''
- else
- WERROR='-Werror'
- fi
-
# Check for -ffunction-sections -fdata-sections
AC_MSG_CHECKING([for g++ that supports -ffunction-sections -fdata-sections])
CXXFLAGS='-g -Werror -ffunction-sections -fdata-sections'
@@ -163,7 +156,6 @@ AC_DEFUN([GLIBCXX_CHECK_COMPILER_FEATURES], [
AC_MSG_RESULT($ac_fdsections)
AC_LANG_RESTORE
- AC_SUBST(WERROR)
AC_SUBST(SECTION_FLAGS)
])
@@ -733,7 +725,7 @@ AC_DEFUN([GLIBCXX_EXPORT_FLAGS], [
# OPTIMIZE_CXXFLAGS = -O3 -fstrict-aliasing -fvtable-gc
AC_SUBST(OPTIMIZE_CXXFLAGS)
- WARN_FLAGS='-Wall -Wextra -Wwrite-strings -Wcast-qual -Wabi'
+ WARN_FLAGS="-Wall -Wextra -Wwrite-strings -Wcast-qual -Wabi=2"
AC_SUBST(WARN_FLAGS)
])
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index 7e1fd84606a..1e0a33fb3ea 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -175,7 +175,7 @@ GLIBCXX_ENABLE_CXX_FLAGS
GLIBCXX_ENABLE_FULLY_DYNAMIC_STRING([no])
GLIBCXX_ENABLE_EXTERN_TEMPLATE([yes])
GLIBCXX_ENABLE_PYTHON
-GLIBCXX_ENABLE_WERROR([yes])
+GLIBCXX_ENABLE_WERROR([no])
GLIBCXX_ENABLE_VTABLE_VERIFY([no])
# Checks for operating systems support that doesn't require linking.
diff --git a/libstdc++-v3/fragment.am b/libstdc++-v3/fragment.am
index 898569520b9..216c572fc60 100644
--- a/libstdc++-v3/fragment.am
+++ b/libstdc++-v3/fragment.am
@@ -14,9 +14,9 @@ toolexecdir = $(glibcxx_toolexecdir)
toolexeclibdir = $(glibcxx_toolexeclibdir)
if ENABLE_WERROR
-WERROR_FLAG=$(WERROR)
+WERROR_FLAG = -Werror
else
-WERROR_FLAG=
+WERROR_FLAG =
endif
if ENABLE_EXTERN_TEMPLATE
diff --git a/libstdc++-v3/src/c++11/debug.cc b/libstdc++-v3/src/c++11/debug.cc
index cb64dd9240e..88fe889dd6a 100644
--- a/libstdc++-v3/src/c++11/debug.cc
+++ b/libstdc++-v3/src/c++11/debug.cc
@@ -66,6 +66,10 @@ namespace
return __gnu_internal::get_mutex(index);
}
+#pragma GCC diagnostic push
+// Suppress -Wabi=2 warnings due to PR c++/51322 mangling change
+#pragma GCC diagnostic warning "-Wabi=6"
+
void
swap_its(__gnu_debug::_Safe_sequence_base& __lhs,
__gnu_debug::_Safe_iterator_base*& __lhs_its,
@@ -90,6 +94,7 @@ namespace
swap_its(__lhs, __lhs._M_const_iterators,
__rhs, __rhs._M_const_iterators);
}
+#pragma GCC diagnostic pop
template<typename _Action>
void
