| Issue |
87956
|
| Summary |
[Flang][OpenMP] Execution does not terminate when the same variable is specified for firstprivate and lastprivate clause in sections construct
|
| Labels |
openmp,
flang
|
| Assignees |
|
| Reporter |
ohno-fj
|
```
Version of flang-new : 19.0.0(cbcdf126ccc774c063b5d5140c1393ff5305dded)/AArch64
```
If the same variable is specified for `firstprivate` and `lastprivate` clause in `sections` construct, the execution does not terminate after about an hour.
Gfortran/ifort completes in less than one second.
If only one of `firstprivate` and `lastprivate` clause is specified, the execution terminates normally.
The following are the test program, Flang-new, Gfortran and ifort compilation/execution result.
omp_PL_SECTIONS_004r_2.f:
```fortran
program main
real*4 ra
integer*4 ib(10), ic , it, ier
integer*4 :: loop=10, loop2=20000, thread=4
!$ integer*4 OMP_GET_MAX_THREADS
!$ integer*4 OMP_GET_THREAD_NUM
ra = 15.
ib = 0
!$ thread = OMP_GET_MAX_THREADS()
!$omp parallel private(it)
!$ it = OMP_GET_THREAD_NUM() + 1
!$omp sections firstprivate(ra) lastprivate(ra)
ib(it)=ib(it)+it
do i=1,loop2
ra=ra+it
enddo
ra=loop2*1
!$omp end sections
!$omp end parallel
end
```
```
$ export OMP_NUM_THREADS=2; flang-new -fopenmp omp_PL_SECTIONS_004r_2.f; time ./a.out
C-c C-c
real 77m46.270s
user 0m0.378s
sys 0m0.040s
$
```
```
$ export OMP_NUM_THREADS=2; gfortran -fopenmp omp_PL_SECTIONS_004r_2.f; time ./a.out
real 0m0.036s
user 0m0.000s
sys 0m0.015s
$
```
```
$ export OMP_NUM_THREADS=2; ifort -qopenmp -diag-disable=10448 omp_PL_SECTIONS_004r_2.f; time ./a.out
real 0m0.070s
user 0m0.006s
sys 0m0.029s
$
```
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