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1// RUN: %clang_cc1 -triple x86_64-pc-linux -verify=expected,array-type -std=c2y -Wall -pedantic -ffreestanding %s2// RUN: %clang_cc1 -triple aarch64-pc-win32 -verify=expected,char-ptr-type -std=c2y -Wall -pedantic -ffreestanding %s3 4/* WG14 N3363: Clang 55 * stdarg.h wording... v36 *7 * Clarifies that va_start can only be used within a function body, and that8 * the macros and functions require an lvalue of type va_list instead of an9 * rvalue.10 *11 * Clang has diagnosed this correctly in all cases except va_copy since12 * Clang 5. va_copy still needs to be updated to issue a diagnostic about use13 * of an rvalue. However, our lack of a diagnostic is still conforming because14 * a diagnostic is not required (it's not a constraint violation).15 */16 17#include <stdarg.h>18 19// The va_list argument given to every macro defined in this subclause shall be20// an lvalue of this type or the result of array-to-pointer decay of such an21// lvalue.22void f(int a, ...) {23 va_list rvalue(); // array-type-error {{function cannot return array type 'va_list' (aka '__builtin_va_list')}}24 va_start(rvalue()); // / char-ptr-type-error {{non-const lvalue reference to type '__builtin_va_list' cannot bind to a temporary of type 'va_list' (aka 'char *')}}25 va_arg(rvalue(), int); // char-ptr-type-error {{expression is not assignable}}26 // FIXME: this should get two diagnostics about use of a non-lvalue.27 va_copy(rvalue(), rvalue()); // char-ptr-type-error {{non-const lvalue reference to type '__builtin_va_list' cannot bind to a temporary of type 'va_list' (aka 'char *')}}28 va_end(rvalue()); // char-ptr-type-error {{non-const lvalue reference to type '__builtin_va_list' cannot bind to a temporary of type 'va_list' (aka 'char *')}}29}30 31// The va_start macro may only be invoked in the compound-statement of the body32// of a variadic function.33void g(va_list ap, int [(va_start(ap), 1)], ...) { // expected-error {{'va_start' cannot be used outside a function}}34 va_end(ap);35}36 37va_list ap;38struct S {39 int array[(va_start(ap), 1)]; // expected-error {{'va_start' cannot be used outside a function}}40};41