c++: Fix up detach clause vs. data-sharing clause checking [PR100319]

The standard says that "The event-handle will be considered as if it
was specified on a firstprivate clause." which means that it can't
be explicitly specified in some other data-sharing clause.
The checking is implemented correctly for C, but for C++ when detach_seen
is true (i.e. the construct had detach clause) we were comparing
OMP_CLAUSE_DECL (c) with t, which was previously initialized to
OMP_CLAUSE_DECL (c), which means it complained about any explicit
data-sharing clause on the same construct with a detach clause.

Fixed by remembering the detach clause in detach_seen (instead of a boolean
flag) and comparing against its OMP_CLAUSE_DECL.

2021-04-29  Jakub Jelinek  <jakub@redhat.com>

	PR c++/100319
	* semantics.c (finish_omp_clauses): Fix up check that variable
	mentioned in detach clause doesn't appear in data-sharing clauses.

	* c-c++-common/gomp/task-detach-3.c: New test.

(cherry picked from commit 1b462deabf70e0f4bebb1f85118827d9c2eeffb5)

diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 4520181d4e594e566dbcb038b49102875991cc6d..3a6468fd5f3b5a4033117207f99f8f65079829e2 100644 (file)
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -6527,7 +6527,7 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
      has been seen, -2 if mixed inscan/normal reduction diagnosed.  */
   int reduction_seen = 0;
   bool allocate_seen = false;
-  bool detach_seen = false;
+  tree detach_seen = NULL_TREE;
   bool mergeable_seen = false;
 
   bitmap_obstack_initialize (NULL);
@@ -7578,7 +7578,7 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
                            type);
                  remove = true;
                }
-             detach_seen = true;
+             detach_seen = c;
              cxx_mark_addressable (t);
            }
          break;
@@ -8548,7 +8548,7 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
              || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
              || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
              || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
-         && OMP_CLAUSE_DECL (c) == t)
+         && OMP_CLAUSE_DECL (c) == OMP_CLAUSE_DECL (detach_seen))
        {
          error_at (OMP_CLAUSE_LOCATION (c),
                    "the event handle of a %<detach%> clause "

diff --git a/gcc/testsuite/c-c++-common/gomp/task-detach-3.c b/gcc/testsuite/c-c++-common/gomp/task-detach-3.c
new file mode 100644 (file)
index 0000000..97e622d
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/gomp/task-detach-3.c
@@ -0,0 +1,19 @@
+/* PR c++/100319 */
+/* { dg-do compile } */
+/* { dg-options "-fopenmp" } */
+
+typedef enum omp_event_handle_t
+{
+  __omp_event_handle_t_max__ = __UINTPTR_MAX__
+} omp_event_handle_t;
+
+extern void omp_fulfill_event (omp_event_handle_t);
+
+void f (omp_event_handle_t x, omp_event_handle_t y, int z)
+{
+  #pragma omp task detach (x) firstprivate (y, z)      /* { dg-bogus "the event handle of a 'detach' clause should not be in a data-sharing clause" } */
+    ;
+
+  #pragma omp task detach (x) shared (y)               /* { dg-bogus "the event handle of a 'detach' clause should not be in a data-sharing clause" } */
+    ;
+}