[Bug sanitizer/57507] New: gcc 4.8: thread sanitizer: std::thread false(?) positive
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57507
Bug ID: 57507
Summary: gcc 4.8: thread sanitizer: std::thread false(?)
positive
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: sanitizer
Assignee: unassigned at gcc dot gnu.org
Reporter: alxchk at alxchk dot me
CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
jakub at gcc dot gnu.org, kcc at gcc dot gnu.org
$ cat test.cpp
#include
int main(int argc, char *argv[])
{
std::thread t([](){});
t.join();
return 0;
}
$ LC_ALL=C g++ --version
g++ (Gentoo Hardened 4.8.0 p1.2, pie-0.5.5) 4.8.0
Copyright (C) 2013 Free Software Foundation, Inc.
$ g++ -o test test.cpp --std=gnu++11 -pthread -fsanitize=thread -ggdb3 -O0
$ ./test
==
WARNING: ThreadSanitizer: data race (pid=14129)
Write of size 8 at 0x7d08bfc8 by thread T1:
#0 :0 (libtsan.so.0+0x00020dc0)
#1 deallocate
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/ext/new_allocator.h:110
(exe+0x2b42)
#2 deallocate
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/alloc_traits.h:377
(exe+0x2972)
#3 _M_destroy
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:417
(exe+0x3336)
#4 :0 (libstdc++.so.6+0x000c8cea)
Previous atomic write of size 4 at 0x7d08bfc8 by main thread:
#0 :0 (libtsan.so.0+0xdfc5)
#1 __exchange_and_add
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/ext/atomicity.h:47
(exe+0x1898)
#2 __exchange_and_add_dispatch
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/ext/atomicity.h:80
(exe+0x1995)
#3 std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release()
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:141
(exe+0x3c86)
#4 std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count()
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:553
(exe+0x3c2d)
#5 std::__shared_ptr::~__shared_ptr()
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:810
(exe+0x3aae)
#6 std::shared_ptr::~shared_ptr()
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr.h:93
(exe+0x3afc)
#7 thread
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/thread:135
(exe+0x1c10)
#8 main /tmp/test.cpp:5 (exe+0x1a3e)
Location is heap block of size 56 at 0x7d08bfc0 allocated by main thread:
#0 :0 (libtsan.so.0+0x00020ad2)
#1 allocate
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/ext/new_allocator.h:104
(exe+0x2a5b)
#2 allocate
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/alloc_traits.h:351
(exe+0x2881)
#3 __shared_count >,
std::allocator > >, std::_Bind_simple >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:519
(exe+0x26e5)
#4
__shared_ptr > >, std::_Bind_simple >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr_base.h:986
(exe+0x25a1)
#5 shared_ptr > >, std::_Bind_simple >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr.h:316
(exe+0x2511)
#6 allocate_shared >,
std::allocator > >, std::_Bind_simple >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr.h:598
(exe+0x2422)
#7 make_shared >, std::_Bind_simple >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/bits/shared_ptr.h:614
(exe+0x225a)
#8 _M_make_routine >
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/thread:193
(exe+0x1fa2)
#9 thread
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4/thread:135
(exe+0x1bde)
#10 main /tmp/test.cpp:5 (exe+0x1a3e)
Thread T1 (tid=14130, running) created by main thread at:
#0 :0 (libtsan.so.0+0x00022cdb)
#1 :0 (libstdc++.so.6+0x000c8ef6)
#2 main /tmp/test.cpp:5 (exe+0x1a3e)
SUMMARY: ThreadSanitizer: data race ??:0 ??
==
ThreadSanitizer: reported 1 warnings
[Bug c++/57437] New: C++11: mutable lambdas; gcc 4.7-4.8
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57437
Bug ID: 57437
Summary: C++11: mutable lambdas; gcc 4.7-4.8
Product: gcc
Version: 4.7.3
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: alxchk at alxchk dot me
> cat test.cpp
#include
#include
int main(int argc, char *argv[])
{
auto x = std::vector({1, 2, 3});
auto y = [x] ()
mutable {
for (auto &i: x)
i ++;
return x;
};
for (const auto &i: y())
std::cout << i << std::endl;
for (const auto &i: y())
std::cout << i << std::endl;
return 0;
}
> x86_64-pc-linux-gnu-g++-4.6.3 -o test test.cpp -std=gnu++0x
> ./test
2
3
4
3
4
5
> LC_ALL=C x86_64-pc-linux-gnu-g++-4.6.3 -v
Using built-in specs.
COLLECT_GCC=x86_64-pc-linux-gnu-g++-4.6.3
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/4.6.3/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/portage/sys-devel/gcc-4.6.3/work/gcc-4.6.3/configure
--prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/4.6.3
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.6.3
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.6.3/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.6.3/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --disable-altivec
--disable-fixed-point --with-ppl --with-cloog --disable-ppl-version-check
--with-cloog-include=/usr/include/cloog-ppl --enable-lto --enable-nls
--without-included-gettext --with-system-zlib --enable-obsolete
--disable-werror --enable-secureplt --enable-multilib --enable-libmudflap
--disable-libssp --enable-esp --enable-libgomp
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/4.6.3/python
--enable-checking=release --disable-libgcj --enable-libstdcxx-time
--enable-languages=c,c++,objc,fortran --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --enable-targets=all
--with-bugurl=http://bugs.gentoo.org/ --with-pkgversion='Gentoo Hardened 4.6.3
p1.11, pie-0.5.2'
Thread model: posix
gcc version 4.6.3 (Gentoo Hardened 4.6.3 p1.11, pie-0.5.2)
> x86_64-pc-linux-gnu-g++-4.7.2 -o test2 test.cpp -std=gnu++0x
> ./test2
2
3
4
> LC_ALL=C x86_64-pc-linux-gnu-g++-4.7.2 -v
Using built-in specs.
COLLECT_GCC=x86_64-pc-linux-gnu-g++-4.7.2
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/4.7.2/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/portage/sys-devel/gcc-4.7.2-r1/work/gcc-4.7.2/configure
--prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/4.7.2
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.2/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.2/include/g++-v4
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --disable-altivec
--disable-fixed-point --with-ppl --with-cloog --disable-ppl-version-check
--with-cloog-include=/usr/include/cloog-ppl --enable-lto --enable-nls
--without-included-gettext --with-system-zlib --enable-obsolete
--disable-werror --enable-secureplt --enable-multilib
--with-multilib-list=m32,m64 --enable-libmudflap --disable-libssp --enable-esp
--enable-libgomp
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/python
--enable-checking=release --disable-libgcj --enable-libstdcxx-time
--enable-languages=c,c++,objc,fortran --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --enable-targets=all
--with-bugurl=http://bugs.gentoo.org/ --with-pkgversion='Gentoo Hardened
4.7.2-r1 p1.5, pie-0.5.5'
Thread model: posix
gcc version 4.7.2 (Gentoo Hardened 4.7.2-r1 p1.5, pie-0.5.5)
> x86_64-pc-linux-gnu-g++-4.8.0 -o test test.cpp -std=gnu++11
> ./test
2
3
4
> LC_ALL=C x86_64-pc-linux-gnu-g++-4.8.0 -v
Using built-in specs.
COLLECT_GCC=x86_64-pc-linux-gnu-g++-4.8.0
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /tmp/portage/sys-devel/gcc-4.8.0/work/gcc-4.8.0/configure
--prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/4.8.0
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.8.0
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.8.0/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.8.0/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/include/g++-v4
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --disable-altivec
--disable-fixed-point --with-ppl --with-cloog --disable-isl-version-check
--with-cloog --enable-lto --enable-nls --w
