https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79321
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2017-02-01
CC| |marxin at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Well, it's not GCC 7 regression, problem is that we generate a GOMP_parallel.
After it's done, the main thread is going to do fork/exec:
#0 __libc_fork () at ../sysdeps/nptl/fork.c:49
#1 0x00000000004ef765 in Perl_my_fork () at util.c:2303
#2 0x00000000004915f6 in Perl_pp_fork () at pp_sys.c:4009
#3 0x00000000004acccd in Perl_runops_standard () at run.c:37
#4 0x0000000000445f28 in S_run_body (oldscope=1) at perl.c:2017
#5 perl_run (my_perl=<optimized out>) at perl.c:1934
#6 0x00000000004034a2 in main (argc=4, argv=0x7fffffffdb88, env=<optimized
out>) at perlmain.c:98
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fae780 (LWP 3579) "perlbench_base." __libc_fork () at
../sysdeps/nptl/fork.c:49
2 Thread 0x7ffff70e6700 (LWP 3583) "perlbench_base." do_spin (val=8,
addr=0x77e044) at ../../../libgomp/config/linux/wait.h:56
3 Thread 0x7ffff68e5700 (LWP 3584) "perlbench_base." futex_wait (val=8,
addr=0x77e044) at ../../../libgomp/config/linux/x86/futex.h:44
4 Thread 0x7ffff60e4700 (LWP 3585) "perlbench_base." futex_wait (val=8,
addr=0x77e044) at ../../../libgomp/config/linux/x86/futex.h:44
and that's why the other threads will not reach the barrier.
