Hi!
During the __builtin_clear_padding implementation, I've noticed we don't
diagnose _ATomic whatever * as last argument to __builtin_*_overflow.
As the storing by that builtin isn't atomic in any way, I think we should
reject it.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2020-11-16 Jakub Jelinek <ja...@redhat.com>
PR c/90628
* c-common.c (check_builtin_function_arguments)
<case BUILT_IN_ADD_OVERFLOW>: Diagnose when last argument is pointer
to _Atomic. For the TYPE_READONLY case, adjust message to be usable
for more builtins and argument positions.
* gcc.dg/builtin-arith-overflow-4.c: New test.
--- gcc/c-family/c-common.c.jj 2020-11-16 19:33:56.458507220 +0100
+++ gcc/c-family/c-common.c 2020-11-16 20:23:15.400194347 +0100
@@ -6133,11 +6133,18 @@ check_builtin_function_arguments (locati
}
else if (TYPE_READONLY (TREE_TYPE (TREE_TYPE (args[2]))))
{
- error_at (ARG_LOCATION (2), "argument 3 in call to function %qE "
- "has pointer to %<const%> type (%qT)", fndecl,
+ error_at (ARG_LOCATION (2), "argument %u in call to function %qE "
+ "has pointer to %qs type (%qT)", 3, fndecl, "const",
TREE_TYPE (args[2]));
return false;
}
+ else if (TYPE_ATOMIC (TREE_TYPE (TREE_TYPE (args[2]))))
+ {
+ error_at (ARG_LOCATION (2), "argument %u in call to function %qE "
+ "has pointer to %qs type (%qT)", 3, fndecl,
+ "_Atomic", TREE_TYPE (args[2]));
+ return false;
+ }
return true;
}
return false;
--- gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c.jj 2020-11-16
20:21:29.859381954 +0100
+++ gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c 2020-11-16
20:27:13.127519307 +0100
@@ -0,0 +1,43 @@
+/* PR c/90628 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+_Atomic int a = 1, b = 2, c = 3;
+_Atomic long d = 4, e = 5, f = 6;
+_Atomic long long g = 7, h = 8, i = 9;
+
+void
+f1 ()
+{
+ __builtin_add_overflow (a, b, &c); /* { dg-error "argument 3 in call to
function '__builtin_add_overflow' has pointer to '_Atomic' type" } */
+}
+
+void
+f2 ()
+{
+ __builtin_sub_overflow (d, e, &f); /* { dg-error "argument 3 in call to
function '__builtin_sub_overflow' has pointer to '_Atomic' type" } */
+}
+
+void
+f3 ()
+{
+ __builtin_mul_overflow (g, h, &i); /* { dg-error "argument 3 in call to
function '__builtin_mul_overflow' has pointer to '_Atomic' type" } */
+}
+
+void
+f4 ()
+{
+ __builtin_sadd_overflow (a, b, &c); /* { dg-warning "passing argument 3 of
'__builtin_sadd_overflow' from incompatible pointer type" } */
+}
+
+void
+f5 ()
+{
+ __builtin_ssubl_overflow (d, e, &f); /* { dg-warning "passing argument 3 of
'__builtin_ssubl_overflow' from incompatible pointer type" } */
+}
+
+void
+f6 ()
+{
+ __builtin_smulll_overflow (g, h, &i); /* { dg-warning "passing
argument 3 of '__builtin_smulll_overflow' from incompatible pointer type" } */
+}
Jakub
