clang/test/Sema/attr-retain.c

   1 // RUN: %clang_cc1 -fsyntax-only -verify %s -Wunused-function
   2
   3 /// We allow 'retain' on non-ELF targets because 'retain' is often used together
   4 /// with 'used'. 'used' has GC root semantics on macOS and Windows. We want
   5 /// users to just write retain,used and don't need to dispatch on binary formats.
   6
   7 extern char test1[] __attribute__((retain));       // expected-warning {{'retain' attribute ignored on a non-definition declaration}}
   8 extern const char test2[] __attribute__((retain)); // expected-warning {{'retain' attribute ignored on a non-definition declaration}}
   9 const char test3[] __attribute__((retain)) = "";
  10
  11 struct __attribute__((retain)) s { // expected-warning {{'retain' attribute only applies to variables with non-local storage, functions, and Objective-C methods}}
  12 };
  13
  14 void foo(void) {
  15   static int a __attribute__((retain));
  16   int b __attribute__((retain)); // expected-warning {{'retain' attribute only applies to variables with non-local storage, functions, and Objective-C methods}}
  17   (void)a;
  18   (void)b;
  19 }
  20
  21 __attribute__((retain,used)) static void f0(void) {}
  22 __attribute__((retain)) static void f1(void) {} // expected-warning {{unused function 'f1'}}
  23 __attribute__((retain)) void f2(void) {}
  24
  25 /// Test attribute merging.
  26 int tentative;
  27 int tentative __attribute__((retain));
  28 extern int tentative;
  29 int tentative = 0;