https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83948
Bug ID: 83948
Summary: Thread safety issue writing to internal file -
libgfortran
Product: gcc
Version: 7.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libfortran
Assignee: unassigned at gcc dot gnu.org
Reporter: longb at cray dot com
Target Milestone: ---
> cat test.f90
subroutine sub (a1, i1, f1, i2, i3, i4, out)
implicit none
character(30),intent(in) :: a1
integer,intent(in) :: i1, i2, i3, i4
real,intent(in) :: f1
character(700), intent(out) :: out
character(700) :: local_out ! local stack variable
write (local_out, "(A,A30,A,I8,A,I8,A,F8.6,A,I3,A,I3)") &
"Same pole re-projecting area source: ", a1, &
': IndexVal=', i1, &
' Indexval*2=', i2, &
' RandomValue=', f1, &
", RandomValue*999=", i3, &
", iThread=", i4
out = local_out
end subroutine sub
program test
use omp_lib
implicit none
integer,parameter :: n = 1000, cn = 700
character(cn) :: table(n)
character(30) :: a1
integer :: i1, i2, i3, i4
real :: f1
integer :: i
!$omp parallel do private (i1, i2, i3, i4, f1, a1)
do i = 1,n
call random_number(f1)
i1 = min(i,99999999)
i2 = min(2*i, 99999999)
i3 = f1*999
i4 = omp_get_thread_num()
a1 = "Beginnng of new record:"
call sub (a1, i1, f1, i2, i3, i4, table(i))
end do
!$omp end parallel do
do i = max(1,n-5), n
print *, "Table element number = ", i, trim(table(i))
end do
end program test
OK : 10 threads
> export OMP_NUM_THREADS=10
> ftn -fopenmp -O3 test.f90
> srun -n1 -c10 ./a.out
Table element number = 995 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 995 Indexval*2= 1990
RandomValue=0.733033, RandomValue*999=732, iThread= 9
Table element number = 996 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 996 Indexval*2= 1992
RandomValue=0.609290, RandomValue*999=608, iThread= 9
Table element number = 997 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 997 Indexval*2= 1994
RandomValue=0.810925, RandomValue*999=810, iThread= 9
Table element number = 998 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 998 Indexval*2= 1996
RandomValue=0.617685, RandomValue*999=617, iThread= 9
Table element number = 999 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 999 Indexval*2= 1998
RandomValue=0.820912, RandomValue*999=820, iThread= 9
Table element number = 1000 Same pole re-projecting area source:
Beginnng of new record: : IndexVal= 1000 Indexval*2= 2000
RandomValue=0.617121, RandomValue*999=616, iThread= 9
Fails: 20 threads
> export OMP_NUM_THREADS=20
> srun -n1 -c20 ./a.out
At line 15 of file test.f90
Internal Error: stash_internal_unit(): Stack Size Exceeded
Error termination. Backtrace:
#0 0x403ca0 in ???
#1 0x403e0f in ???
#2 0x4059cd in gomp_thread_start
at
../../../cray-gcc-7.2.0-201709081833.7aac99f36ce61/libgomp/team.c:120
#3 0x41a263 in start_thread
at /home/abuild/rpmbuild/BUILD/glibc-2.22/nptl/pthread_create.c:334
#4 0x4a1488 in ???
at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
#5 0xffffffffffffffff in ???
