C++, OpenMP: Handle ARRAY_TYPE array sections, not just pointers

This patch is a bug fix for commit gcc-17-202-g3f8c7483112, 'OpenMP:
Expand "declare mapper" mappers for target {enter,exit,} data
directives'.  The ChangeLog for that patch indicated that
cxx_omp_map_array_section was supposed to accept both arrays and
pointers as the base expression, but the code actually only allowed
pointers.  OTOH, both the error-checking in handle_omp_array_sections_1
and the code generation in build_array_ref allow ARRAY_TYPE, and code with
such expressions is actually coming in to the function.

There is no test case included with this patch, but I ran across this
in the two new test cases included with the OpenMP iterators patch
https://gcc.gnu.org/pipermail/gcc-patches/2025-July/689071.html which
I am preparing to resubmit.

gcc/cp/ChangeLog
	* semantics.cc (cxx_omp_map_array_section): Allow ARRAY_TYPE
	expressions, not just pointers.

diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 565117fb8fa8384a510d2ef7b91f2b361748026b..42278d336bf06d4d6360e948e8cd6d8e6fdc15b9 100644 (file)
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -6950,9 +6950,11 @@ cxx_omp_map_array_section (location_t loc, tree t)
       if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
        t = convert_from_reference (t);
 
-      if (TYPE_PTR_P (TREE_TYPE (t)))
+      if (TYPE_PTR_P (TREE_TYPE (t))
+         || TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
        t = build_array_ref (loc, t, low);
       else
+       /* handle_omp_array_sections_1 has already diagnosed the error.  */
        t = error_mark_node;
     }