llvm-project/clang/test/Sema/pointer-subtract-compat.c

// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic

typedef const char rchar;
int a(char* a, rchar* b) {
  return a-b;
}

void f0(void (*fp)(void)) {
  int x = fp - fp; // expected-warning{{arithmetic on pointers to the function type 'void (void)' is a GNU extension}}
}
Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'. - This is designed to make it obvious that %clang_cc1 is a "test variable" which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it can be useful to redefine what gets run as 'clang -cc1' (for example, to set a default target). llvm-svn: 91446 2009-12-15 20:14:24 +00:00			`// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic`
Make sure to take the unqualified versions of the canonical types for type-checking pointer subtraction; if the canonical types aren't used, the qualifiers won't always get stripped off correctly. llvm-svn: 55620 2008-09-02 05:09:35 +00:00
			`typedef const char rchar;`
			`int a(char* a, rchar* b) {`
			`return a-b;`
			`}`
Allow subtraction of function pointer types in C, as a GNU extension. Fixes rdar://problem/6520707 llvm-svn: 62859 2009-01-23 19:03:35 +00:00
			`void f0(void (*fp)(void)) {`
Factor out (some of) the checking for invalid forms of pointer arithmetic into a couple of common routines. Use these to make the messages more consistent in the various contexts, especially in terms of consistently diagnosing binary operators with invalid types on both the left- and right-hand side. Also, improve the grammar and wording of the messages some, handling both two pointers and two (different) types. The wording of function pointer arithmetic diagnostics still strikes me as poorly phrased, and I worry this makes them slightly more awkward if more consistent. I'm hoping to fix that with a follow-on patch and test case that will also make them more helpful when a typedef or template type parameter makes the type completely opaque. Suggestions on better wording are very welcome, thanks to Richard Smith for some initial help on that front. llvm-svn: 133906 2011-06-27 08:02:19 +00:00			`int x = fp - fp; // expected-warning{{arithmetic on pointers to the function type 'void (void)' is a GNU extension}}`
Allow subtraction of function pointer types in C, as a GNU extension. Fixes rdar://problem/6520707 llvm-svn: 62859 2009-01-23 19:03:35 +00:00			`}`