|  | // RUN: %clang_cc1 -fsyntax-only -Wextra -std=c++2a -verify %s | 
|  | // RUN: %clang_cc1 -fsyntax-only -Wextra-semi-stmt -std=c++2a -verify %s | 
|  | // RUN: %clang_cc1 -fsyntax-only -Wempty-init-stmt -std=c++2a -verify %s | 
|  | // RUN: cp %s %t | 
|  | // RUN: %clang_cc1 -x c++ -Wempty-init-stmt -std=c++2a -fixit %t | 
|  | // RUN: %clang_cc1 -x c++ -Wempty-init-stmt -std=c++2a -Werror %t | 
|  |  | 
|  | struct S { | 
|  | int *begin(); | 
|  | int *end(); | 
|  | }; | 
|  |  | 
|  | void naive(int x) { | 
|  | if (; true) // expected-warning {{empty initialization statement of 'if' has no effect}} | 
|  | ; | 
|  |  | 
|  | switch (; x) { // expected-warning {{empty initialization statement of 'switch' has no effect}} | 
|  | } | 
|  |  | 
|  | for (; int y : S()) // expected-warning {{empty initialization statement of 'range-based for' has no effect}} | 
|  | ; | 
|  |  | 
|  | for (;;) // OK | 
|  | ; | 
|  | } | 
|  |  | 
|  | #define NULLMACRO | 
|  |  | 
|  | void with_null_macro(int x) { | 
|  | if (NULLMACRO; true) | 
|  | ; | 
|  |  | 
|  | switch (NULLMACRO; x) { | 
|  | } | 
|  |  | 
|  | for (NULLMACRO; int y : S()) | 
|  | ; | 
|  | } | 
|  |  | 
|  | #define SEMIMACRO ; | 
|  |  | 
|  | void with_semi_macro(int x) { | 
|  | if (SEMIMACRO true) | 
|  | ; | 
|  |  | 
|  | switch (SEMIMACRO x) { | 
|  | } | 
|  |  | 
|  | for (SEMIMACRO int y : S()) | 
|  | ; | 
|  | } | 
|  |  | 
|  | #define PASSTHROUGHMACRO(x) x | 
|  |  | 
|  | void with_passthrough_macro(int x) { | 
|  | if (PASSTHROUGHMACRO(;) true) | 
|  | ; | 
|  |  | 
|  | switch (PASSTHROUGHMACRO(;) x) { | 
|  | } | 
|  |  | 
|  | for (PASSTHROUGHMACRO(;) int y : S()) | 
|  | ; | 
|  | } |