Hi!
As the testcase shows, we would ICE if the type of the first argument of
various atomic builtins was pointer to (non-void) incomplete type, we would
assume that TYPE_SIZE_UNIT must be non-NULL. This patch diagnoses it
instead. And also changes the TREE_CODE != INTEGER_CST check to
!tree_fits_uhwi_p, as we use tree_to_uhwi after this and at least in theory
the int could be too large and not fit.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2020-08-10 Jakub Jelinek <ja...@redhat.com>
PR c/96545
* c-common.c (get_atomic_generic_size): Require that first argument's
type points to a complete type and use tree_fits_uhwi_p instead of
just INTEGER_CST TREE_CODE check for the TYPE_SIZE_UNIT.
* c-c++-common/pr96545.c: New test.
--- gcc/c-family/c-common.c.jj 2020-07-31 23:07:00.566153515 +0200
+++ gcc/c-family/c-common.c 2020-08-10 12:03:35.236841534 +0200
@@ -7017,8 +7017,15 @@ get_atomic_generic_size (location_t loc,
return 0;
}
+ if (!COMPLETE_TYPE_P (TREE_TYPE (type_0)))
+ {
+ error_at (loc, "argument 1 of %qE must be a pointer to a complete type",
+ function);
+ return 0;
+ }
+
/* Types must be compile time constant sizes. */
- if (TREE_CODE ((TYPE_SIZE_UNIT (TREE_TYPE (type_0)))) != INTEGER_CST)
+ if (!tree_fits_uhwi_p ((TYPE_SIZE_UNIT (TREE_TYPE (type_0)))))
{
error_at (loc,
"argument 1 of %qE must be a pointer to a constant size type",
--- gcc/testsuite/c-c++-common/pr96545.c.jj 2020-08-10 12:28:43.296222401
+0200
+++ gcc/testsuite/c-c++-common/pr96545.c 2020-08-10 12:28:28.258428487
+0200
@@ -0,0 +1,31 @@
+/* PR c/96545 */
+/* { dg-do compile } */
+
+extern char x[], y[], z[];
+struct S;
+extern struct S s, t, u;
+int v, w;
+
+void
+foo (void)
+{
+ __atomic_exchange (&x, &y, &z, 0); /* { dg-error "must be a pointer to a
complete type" } */
+}
+
+void
+bar (void)
+{
+ __atomic_exchange (&s, &t, &u, 0); /* { dg-error "must be a pointer to a
complete type" } */
+}
+
+void
+baz (void)
+{
+ __atomic_exchange (&v, &t, &w, 0); /* { dg-error "size mismatch in
argument 2 of" } */
+}
+
+void
+qux (void)
+{
+ __atomic_exchange (&v, &w, &t, 0); /* { dg-error "size mismatch in
argument 3 of" } */
+}
Jakub
