1 // RUN: %clang_cc1 -std=c89 -verify %s
2 // RUN: %clang_cc1 -std=c99 -verify %s
3 // RUN: %clang_cc1 -std=c11 -verify %s
4 // RUN: %clang_cc1 -std=c17 -verify %s
5 // RUN: %clang_cc1 -std=c23 -verify %s
6
7 // expected-no-diagnostics
8
9 /* WG14 ???: yes
10 * new block scopes for selection and iteration statements
11 *
12 * This is referenced in the C99 front matter as new changes to C99, but it is
13 * not clear which document number introduced the changes. It's possible this
14 * is WG14 N759, based on discussion in the C99 rationale document that claims
15 * these changes were made in response to surprising issues with the lifetime
16 * of compound literals in compound statements vs non-compound statements.
17 */
18
19 enum {a, b};
different(void)20 void different(void) {
21 if (sizeof(enum {b, a}) != sizeof(int)) {
22 _Static_assert(a == 1, "");
23 }
24 /* In C89, the 'b' found here would have been from the enum declaration in
25 * the controlling expression of the selection statement, not from the global
26 * declaration. In C99 and later, that enumeration is scoped to the 'if'
27 * statement and the global declaration is what's found.
28 */
29 #if __STDC_VERSION__ >= 199901L
30 _Static_assert(b == 1, "");
31 #else
32 _Static_assert(b == 0, "");
33 #endif
34 }
35
36