https://gcc.gnu.org/g:28d20a591ddf1618d75f2b8261ba85bf15a49876
commit r16-5008-g28d20a591ddf1618d75f2b8261ba85bf15a49876 Author: Tobias Burnus <[email protected]> Date: Mon Nov 3 18:30:07 2025 +0100 libgomp.fortran/omp_target_memset.f90 - Avoid implicit mapping by an uninit size [PR122543] In OpenMP, pointers are implicitly mapped - which means for Fortran that their pointer target is also mapped. However, for uninitialized memory, this means that some random pointee with some random amount of memory is copied - in the good case, size == 0, but if not, odd things can happen. Solution: Use 'fptr => null()' before the target mapping or - as done here - declare the pointer inside the region. libgomp/ChangeLog: PR libgomp/122543 * testsuite/libgomp.fortran/omp_target_memset.f90: Move fptr inside the target to avoid implicit mapping of its uninit pointee. * testsuite/libgomp.fortran/omp_target_memset-2.f90: Likewise. Diff: --- libgomp/testsuite/libgomp.fortran/omp_target_memset-2.f90 | 11 ++++++++--- libgomp/testsuite/libgomp.fortran/omp_target_memset.f90 | 6 ++++-- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/libgomp/testsuite/libgomp.fortran/omp_target_memset-2.f90 b/libgomp/testsuite/libgomp.fortran/omp_target_memset-2.f90 index 2641086f60d8..78c66d3bbc9d 100644 --- a/libgomp/testsuite/libgomp.fortran/omp_target_memset-2.f90 +++ b/libgomp/testsuite/libgomp.fortran/omp_target_memset-2.f90 @@ -11,7 +11,6 @@ do dev = omp_initial_device, omp_get_num_devices () block integer(c_int) :: i, val, start, tail type(c_ptr) :: ptr, ptr2, tmpptr - integer(c_int8_t), pointer, contiguous :: fptr(:) integer(c_intptr_t) :: intptr integer(c_size_t), parameter :: count = 1024 integer(omp_depend_kind) :: dep(1) @@ -35,22 +34,28 @@ block !$omp taskwait !$omp target device(dev) is_device_ptr(ptr) depend(depobj: dep(1)) nowait + block + integer(c_int8_t), pointer, contiguous :: fptr(:) + call c_f_pointer (ptr, fptr, [count]) do i = 1 + start, int(count, c_int) - start - tail - call c_f_pointer (ptr, fptr, [count]) if (fptr(i) /= int (val, c_int8_t)) stop 2 fptr(i) = fptr(i) + 2_c_int8_t end do + end block !$omp end target ptr2 = omp_target_memset_async (tmpptr, val + 3, & count - start - tail, dev, 1, dep) !$omp target device(dev) is_device_ptr(ptr) depend(depobj: dep(1)) nowait + block + integer(c_int8_t), pointer, contiguous :: fptr(:) + call c_f_pointer (ptr, fptr, [count]) do i = 1 + start, int(count, c_int) - start - tail - call c_f_pointer (ptr, fptr, [count]) if (fptr(i) /= int (val + 3, c_int8_t)) stop 3 fptr(i) = fptr(i) - 1_c_int8_t end do + end block !$omp end target ptr2 = omp_target_memset_async (tmpptr, val - 3, & diff --git a/libgomp/testsuite/libgomp.fortran/omp_target_memset.f90 b/libgomp/testsuite/libgomp.fortran/omp_target_memset.f90 index 1ee184ac47c1..91a6baa7e5cd 100644 --- a/libgomp/testsuite/libgomp.fortran/omp_target_memset.f90 +++ b/libgomp/testsuite/libgomp.fortran/omp_target_memset.f90 @@ -6,7 +6,6 @@ implicit none (type, external) integer(c_int) :: dev, i, val, start, tail type(c_ptr) :: ptr, ptr2, tmpptr -integer(c_int8_t), pointer, contiguous :: fptr(:) integer(c_intptr_t) :: intptr integer(c_size_t), parameter :: count = 1024 @@ -26,10 +25,13 @@ do dev = omp_initial_device, omp_get_num_devices () if (.not. c_associated (tmpptr, ptr2)) stop 1 !$omp target device(dev) is_device_ptr(ptr) + block + integer(c_int8_t), pointer, contiguous :: fptr(:) + call c_f_pointer (ptr, fptr, [count]) do i = 1 + start, int(count, c_int) - start - tail - call c_f_pointer (ptr, fptr, [count]) if (fptr(i) /= int (val, c_int8_t)) stop 2 end do + end block !$omp end target end do end do
