test/Preprocessor/undef-error.c - clang - Git at Google

 // RUN: %clang_cc1 %s -pedantic-errors -verify
 // PR2045

 #define b
 /* expected-error {{extra tokens at end of #undef directive}} */ #undef a b
	// RUN: %clang_cc1 %s -pedantic-errors -verify
	// PR2045

	#define b
	/* expected-error {{extra tokens at end of #undef directive}} */ #undef a b