c: Fully fold each parameter for call to .ACCESS_WITH_SIZE [PR119717]

C_MAYBE_CONST_EXPR is a C FE operator that will be removed by c_fully_fold.
In c_fully_fold, it assumes that operands of function calls have already
been folded. However, when we build call to .ACCESS_WITH_SIZE, all its
operands are not fully folded. therefore the C FE specific operator is
passed to middle-end.

In order to fix this issue, fully fold the parameters before building the
call to .ACCESS_WITH_SIZE.

	PR c/119717

gcc/c/ChangeLog:

	* c-typeck.cc (build_access_with_size_for_counted_by): Fully fold the
	parameters for call to .ACCESS_WITH_SIZE.

gcc/testsuite/ChangeLog:

	* gcc.dg/pr119717.c: New test.

2 files changed, 30 insertions, 2 deletions

diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index 3870e8a..55d896e 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -3013,12 +3013,16 @@ build_access_with_size_for_counted_by (location_t loc, tree ref,
   gcc_assert (c_flexible_array_member_type_p (TREE_TYPE (ref)));
   /* The result type of the call is a pointer to the flexible array type.  */
   tree result_type = c_build_pointer_type (TREE_TYPE (ref));
+  tree first_param
+    = c_fully_fold (array_to_pointer_conversion (loc, ref), false, NULL);
+  tree second_param
+    = c_fully_fold (counted_by_ref, false, NULL);
 
   tree call
     = build_call_expr_internal_loc (loc, IFN_ACCESS_WITH_SIZE,
 				    result_type, 6,
-				    array_to_pointer_conversion (loc, ref),
-				    counted_by_ref,
+				    first_param,
+				    second_param,
 				    build_int_cst (integer_type_node, 1),
 				    build_int_cst (counted_by_type, 0),
 				    build_int_cst (integer_type_node, -1),
diff --git a/gcc/testsuite/gcc.dg/pr119717.c b/gcc/testsuite/gcc.dg/pr119717.c
new file mode 100644
index 0000000..e5eedc5
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr119717.c
@@ -0,0 +1,24 @@
+/* PR c/119717  */
+/* { dg-additional-options "-std=c23" } */
+/* { dg-do compile } */
+
+struct annotated {
+  unsigned count;
+  [[gnu::counted_by(count)]] char array[];
+};
+
+[[gnu::noinline,gnu::noipa]]
+static unsigned
+size_of (bool x, struct annotated *a)
+{
+  char *p = (x ? a : 0)->array;
+  return __builtin_dynamic_object_size (p, 1);
+}
+
+int main()
+{
+  struct annotated *p = __builtin_malloc(sizeof *p);
+  p->count = 0;
+  __builtin_printf ("the bdos whole is %ld\n", size_of (0, p));
+  return 0;
+}