Ref: https://gcc.gnu.org/pipermail/fortran/2026-February/063551.html
See attached.
Awaiting approval.
From 9db159f5a09d5beb0d0545e573fcdfaa8938088d Mon Sep 17 00:00:00 2001
From: Andre Vehreschild <[email protected]>
Date: Sat, 14 Feb 2026 11:37:07 -0800
Subject: [PATCH] Fortran: Fix coarray shared mem [PR121429]
PR fortran/121429
libgfortran/ChangeLog:
* caf/shmem.c (_gfortran_caf_deregister): Add a call to
sync_team.
gcc/testsuite/ChangeLog:
* gfortran.dg/coarray/deallocate_sync.f90: New test.
---
.../gfortran.dg/coarray/deallocate_sync.f90 | 26 +++++++++++++++++++
libgfortran/caf/shmem.c | 1 +
2 files changed, 27 insertions(+)
create mode 100644 gcc/testsuite/gfortran.dg/coarray/deallocate_sync.f90
diff --git a/gcc/testsuite/gfortran.dg/coarray/deallocate_sync.f90 b/gcc/testsuite/gfortran.dg/coarray/deallocate_sync.f90
new file mode 100644
index 00000000000..8c6f2b79fb1
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/coarray/deallocate_sync.f90
@@ -0,0 +1,26 @@
+! { dg-do run }
+! Test case from pr121429 which failed because the deallocate was not
+! doing an implicit sync all.
+program main
+ implicit none
+ integer, allocatable, codimension[:] :: a(:), b(:)
+ integer :: n, i, left, right
+ integer :: k
+ n = num_images()
+ i = this_image()
+ ! We skip this test for -fcoarray=single
+ if (n .ne. 1) then
+ ! Verify in the testsuite that num_images = 8 as set in caf.exp
+ if (n .ne. 8) error stop "Need at least three images"
+ left = modulo(i+n-2,n)+1
+ right = modulo(i,n)+1
+ do k=1,1000
+ allocate(a(k+5)[*])
+ allocate(b(k)[*])
+ b(:)[right] = right + 1000 * k
+ deallocate (a) ! This synchronizes automatically
+ if (any(b(:)[left] /= left + 1000 * k)) error stop "Test failed"
+ deallocate (b)
+ end do
+ end if
+end program main
diff --git a/libgfortran/caf/shmem.c b/libgfortran/caf/shmem.c
index 9913db6d709..de6a2b23017 100644
--- a/libgfortran/caf/shmem.c
+++ b/libgfortran/caf/shmem.c
@@ -465,6 +465,7 @@ _gfortran_caf_deregister (caf_token_t *token, caf_deregister_t type, int *stat,
free (ca);
free (TOKEN (*token));
*token = NULL;
+ sync_team (caf_current_team);
}
else
{
--
2.53.0