A recent committ caused the following build failure with the
x86_64-pc-mingw32 target:
make[4]: Entering directory
`/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src'
/bin/sh ../libtool --tag CXX --mode=compile
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/./gcc/xgcc -shared-libgcc
-B/var/tmp/build/gcc-svn/build-x86_64-pc-linux/./gcc -nostdinc++
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src/.libs
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/winsup/mingw
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/winsup/w32api/lib
-isystem /var/tmp/build/gcc-svn/gcc/winsup/mingw/include -isystem
/var/tmp/build/gcc-svn/gcc/winsup/w32api/include
-B/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/bin/
-B/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/lib/ -isystem
/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/include -isystem
/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/sys-include
-I/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/x86_64-pc-mingw32
-I/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include
-I/var/tmp/build/gcc-svn/gcc/libstdc++-v3/libsupc++
-fno-implicit-templates -Wall -Wextra -Wwrite-strings -Wcast-qual
-fdiagnostics-show-location=once -ffunction-sections -fdata-sections
-g -O2 -std=gnu++0x -c ../../../../gcc/libstdc++-v3/src/mutex.cc
libtool: compile:
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/./gcc/xgcc -shared-libgcc
-B/var/tmp/build/gcc-svn/build-x86_64-pc-linux/./gcc -nostdinc++
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src/.libs
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/winsup/mingw
-L/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/winsup/w32api/lib
-isystem /var/tmp/build/gcc-svn/gcc/winsup/mingw/include -isystem
/var/tmp/build/gcc-svn/gcc/winsup/w32api/include
-B/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/bin/
-B/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/lib/ -isystem
/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/include -isystem
/var/tmp/root-x86_64-pc-linux/x86_64-pc-mingw32/sys-include
-I/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/x86_64-pc-mingw32
-I/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include
-I/var/tmp/build/gcc-svn/gcc/libstdc++-v3/libsupc++
-fno-implicit-templates -Wall -Wextra -Wwrite-strings -Wcast-qual
-fdiagnostics-show-location=once -ffunction-sections -fdata-sections
-g -O2 -std=gnu++0x -c ../../../../gcc/libstdc++-v3/src/mutex.cc
-DDLL_EXPORT -DPIC -o .libs/mutex.o
In file included from ../../../../gcc/libstdc++-v3/src/mutex.cc:30:
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:
In constructor 'std::mutex::mutex()':
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:66:
error: void value not ignored as it ought to be
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:
In constructor 'std::recursive_mutex::recursive_mutex()':
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:129:
error: void value not ignored as it ought to be
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:
In constructor 'std::once_flag::once_flag()':
/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/include/mutex:363:
error: expected primary-expression before '{' token
make[4]: *** [mutex.lo] Error 1
make[4]: Leaving directory
`/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3/src'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory
`/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3'
make[2]: *** [all] Error 2
make[2]: Leaving directory
`/var/tmp/build/gcc-svn/build-x86_64-pc-linux/x86_64-pc-mingw32/libstdc++-v3'
make[1]: *** [all-target-libstdc++-v3] Error 2
make[1]: Leaving directory `/var/tmp/build/gcc-svn/build-x86_64-pc-linux'
make: *** [all] Error 2
