[gcc r14-9446] OpenMP/Fortran: Fix defaultmap(none) issue with dummy procedures [PR114283]

[gcc r14-9446] OpenMP/Fortran: Fix defaultmap(none) issue with dummy procedures [PR114283]

[Tobias Burnus]

https://gcc.gnu.org/g:c5037fcee2de438774466e78e46e6ab4df72a7fe

commit r14-9446-gc5037fcee2de438774466e78e46e6ab4df72a7fe
Author: Tobias Burnus <tburnus@baylibre.com>
Date:   Wed Mar 13 09:35:28 2024 +0100

    OpenMP/Fortran: Fix defaultmap(none) issue with dummy procedures [PR114283]
    
    Dummy procedures look similar to variables but aren't - neither in Fortran
    nor in OpenMP. As the middle end sees PARM_DECLs, mark them as predetermined
    firstprivate for mapping (as already done in gfc_omp_predetermined_sharing).
    
    This does not address the isses related to procedure pointers, which are
    still discussed on spec level [see PR].
    
            PR fortran/114283
    
    gcc/fortran/ChangeLog:
    
            * trans-openmp.cc (gfc_omp_predetermined_mapping): Map dummy
            procedures as firstprivate.
    
    libgomp/ChangeLog:
    
            * testsuite/libgomp.fortran/declare-target-indirect-4.f90: New test.

Diff:
---
 gcc/fortran/trans-openmp.cc                        |  9 +++++
 .../libgomp.fortran/declare-target-indirect-4.f90  | 43 ++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/gcc/fortran/trans-openmp.cc b/gcc/fortran/trans-openmp.cc
index a2bf15665b3..1dba47126ed 100644
--- a/gcc/fortran/trans-openmp.cc
+++ b/gcc/fortran/trans-openmp.cc
@@ -343,6 +343,15 @@ gfc_omp_predetermined_mapping (tree decl)
 	    && GFC_DECL_SAVED_DESCRIPTOR (decl)))
     return OMP_CLAUSE_DEFAULTMAP_TO;
 
+  /* Dummy procedures aren't considered variables by OpenMP, thus are
+     disallowed in OpenMP clauses.  They are represented as PARM_DECLs
+     in the middle-end, so return OMP_CLAUSE_DEFAULTMAP_FIRSTPRIVATE here
+     to avoid complaining about their uses with defaultmap(none).  */
+  if (TREE_CODE (decl) == PARM_DECL
+      && TREE_CODE (TREE_TYPE (decl)) == POINTER_TYPE
+      && TREE_CODE (TREE_TYPE (TREE_TYPE (decl))) == FUNCTION_TYPE)
+    return OMP_CLAUSE_DEFAULTMAP_FIRSTPRIVATE;
+
   /* These are either array or derived parameters, or vtables.  */
   if (VAR_P (decl) && TREE_READONLY (decl)
       && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
diff --git a/libgomp/testsuite/libgomp.fortran/declare-target-indirect-4.f90 b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-4.f90
new file mode 100644
index 00000000000..43f4295494c
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-4.f90
@@ -0,0 +1,43 @@
+! { dg-additional-options "-fdump-tree-gimple" }
+
+! PR fortran/114283
+
+! { dg-final { scan-tree-dump "#pragma omp parallel shared\\(i\\) if\\(0\\) default\\(none\\) firstprivate\\(g\\)" "gimple" } }
+! { dg-final { scan-tree-dump "#pragma omp target num_teams\\(-2\\) thread_limit\\(0\\) firstprivate\\(h\\) map\\(from:j \\\[len: 4\\\]\\) defaultmap\\(none\\)" "gimple" } }
+
+
+module m
+  implicit none (type, external)
+  !$omp declare target indirect enter(f1, f2)
+contains
+  integer function f1 ()
+    f1 = 99
+  end
+  integer function f2 ()
+    f2 = 89
+  end
+end module m
+
+use m
+implicit none (type, external)
+call sub1(f1)
+call sub2(f2)
+contains
+  subroutine sub1(g)
+    procedure(integer) :: g
+    integer :: i
+    !$omp parallel default(none) if(.false.) shared(i)
+      i = g ()
+    !$omp end parallel
+    if (i /= 99) stop 1
+  end
+
+  subroutine sub2(h)
+    procedure(integer) :: h
+    integer :: j
+    !$omp target defaultmap(none) map(from:j)
+      j = h ()
+    !$omp end target
+    if (j /= 89) stop 1
+  end
+end