https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80038
Bug ID: 80038
Summary: Random segfault using local vectors in Cilk function
Product: gcc
Version: 6.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: florent.hivert at lri dot fr
Target Milestone: ---
The following (reduced) code works if using only one core but segfault randomly
when using more core. The more core your have, the more chance you have to get
a segfault. Sometime it also fail with a double free error.
I compiled it using
g++-6 -std=c++11 -fcilkplus -g -Wall -lcilkrts red2.cpp -o red2
#include <vector>
#include <cilk/cilk.h>
void walk(std::vector<int> v, unsigned size) {
if (v.size() < size)
for (int i=0; i<8; i++) {
std::vector<int> vnew(v);
vnew.push_back(i);
cilk_spawn walk(vnew, size);
}
}
int main(int argc, char **argv) {
std::vector<int> v{};
walk(v, 5);
}
FWIW:
$ g++-6 -v
Using built-in specs.
COLLECT_GCC=g++-6
COLLECT_LTO_WRAPPER=/usr/lib64/gcc/x86_64-suse-linux/6/lto-wrapper
Target: x86_64-suse-linux
Configured with: ../configure --prefix=/usr --infodir=/usr/share/info
--mandir=/usr/share/man --libdir=/usr/lib64 --libexecdir=/usr/lib64
--enable-languages=c,c++,objc,fortran,obj-c++,java,ada,go
--enable-offload-targets=hsa --enable-checking=release
--with-gxx-include-dir=/usr/include/c++/6 --enable-ssp --disable-libssp
--disable-libvtv --disable-libcc1 --disable-plugin
--with-bugurl=http://bugs.opensuse.org/ --with-pkgversion='SUSE Linux'
--disable-libgcj --with-slibdir=/lib64 --with-system-zlib --enable-__cxa_atexit
--enable-libstdcxx-allocator=new --disable-libstdcxx-pch
--with-default-libstdcxx-abi=gcc4-compatible
--enable-version-specific-runtime-libs --enable-linker-build-id
--enable-linux-futex --enable-gnu-indirect-function --program-suffix=-6
--without-system-libunwind --enable-multilib --with-arch-32=x86-64
--with-tune=generic --build=x86_64-suse-linux --host=x86_64-suse-linux
Thread model: posix
gcc version 6.3.1 20170202 [gcc-6-branch revision 245119] (SUSE Linux)
