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From: "jason at cornsyrup dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/52590] New: std::thread Segmentation fault static linking
Date: Wed, 14 Mar 2012 20:42:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52590

             Bug #: 52590
           Summary: std::thread Segmentation fault static linking
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jason@cornsyrup.org


$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.7/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.7.0~rc1-1ubuntu1' --with-bugurl=file:///usr/share/doc/gcc-4.7/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr
--program-suffix=-4.7 --enable-shared --enable-linker-build-id
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.7
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin
--enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 4.7.0 20120302 (prerelease) (Ubuntu/Linaro 4.7.0~rc1-1ubuntu1) 

$ g++ -static -pthread -std=c++0x -o thread thread.cc 

$ ./thread 
pthread_create works
std::thread works
Segmentation fault

$ cat thread.cc 
#include <thread>
#include <iostream>

void *foo1(void *) {
    std::cout << "pthread_create works\n";
    return 0;
}

void foo2() {
    std::cout << "std::thread works\n";
}

int main() {
    {
        pthread_t t;
        pthread_create(&t, 0, foo1, 0);
        void *r;
        pthread_join(t, &r);
    }

    {
        std::thread t(foo2);
        t.join();
    }
    return 0;
}

I was surprised to see that pthreads worked in this case while std::thread did
not. I've also heard that boost::thread works. I'm having a hard time finding
any documentation on whether static linking and std::thread should work
together. Also see
http://stackoverflow.com/questions/7090623/c0x-thread-static-linking-problem

If it is the case that pthreads and std::thread cannot work together with
static linking, then it'd be nice to fail at some point before runtime if that
is possible.