gcc/testsuite/gcc.dg/attr-copy-6.c

   1 /* PR middle-end/88546 - Copy attribute unusable for weakrefs
   2    { dg-do compile }
   3    { dg-skip-if "Attributes not supported" { { hppa*-*-hpux* } && { ! lp64 } } }
   4    { dg-options "-O2 -Wall" }
   5    { dg-require-visibility "hidden" }
   6    { dg-require-alias "" }
   7    { dg-require-weak "" } */
   8
   9 #define ATTR(...)   __attribute__ ((__VA_ARGS__))
  10 #define ASRT(expr)   _Static_assert (expr, #expr)
  11
  12 /* Variable that is local to this translation unit but that can
  13    be modified from other units by calling reset_unit_local().  */
  14 static int unit_local;
  15
  16 void reset_unit_local (void)
  17 {
  18   unit_local = 0;
  19 }
  20
  21 /* Attribute leaf implies that fleaf() doesn't modify unit_local().  */
  22 ATTR (leaf, returns_nonnull)
  23 void* fleaf_retnz (void);
  24
  25 /* Verify both attributes have been applied.  */
  26 ASRT (__builtin_has_attribute (fleaf_retnz, leaf));
  27 ASRT (__builtin_has_attribute (fleaf_retnz, returns_nonnull));
  28
  29 /* Verify that attribute leaf has the expected effect.  */
  30 void call_fleaf_retnz (void)
  31 {
  32   int i = unit_local;
  33   void *p = fleaf_retnz ();
  34
  35   /* Expect both tests to be folded to false and the calls eliminated.  */
  36   extern void call_fleaf_retnz_test_leaf_eliminated (void);
  37   if (i != unit_local)
  38     call_fleaf_retnz_test_leaf_eliminated ();
  39
  40   extern void call_fleaf_retnz_test_nonnull_eliminated (void);
  41   if (p == 0)
  42     call_fleaf_retnz_test_nonnull_eliminated ();
  43 }
  44
  45
  46 /* Verify that attribute copy copies the returns_nonnull attribute
  47    but doesn't try to copy attribute leaf which only applies to extern
  48    function.  */
  49 static ATTR (copy (fleaf_retnz), weakref ("fleaf_retnz"))
  50 void* fweakref_fleaf_retnz_copy (void);
  51
  52 ASRT (!__builtin_has_attribute (fweakref_fleaf_retnz_copy, leaf));
  53 ASRT (__builtin_has_attribute (fweakref_fleaf_retnz_copy, returns_nonnull));
  54
  55 void call_fweakref_fleaf_retnz_copy (void)
  56 {
  57   int i = unit_local;
  58   void *p = fweakref_fleaf_retnz_copy ();
  59
  60   /* Since leaf is not copied, expect the following test not to be
  61      folded and the call to be emitted.  */
  62   extern void call_fweakref_test_leaf_emitted (void);
  63   if (i != unit_local)
  64     call_fweakref_test_leaf_emitted ();
  65
  66   /* Expect the following test to be folded to false and the call
  67      eliminated.  */
  68   extern void call_fweakref_fleaf_nonnull_eliminated (void);
  69   if (p == 0)
  70     call_fweakref_fleaf_nonnull_eliminated ();
  71 }
  72
  73 /* This is reduced from libgfortran/runtime/error.c.  Verify it
  74    doesn't trigger warnings and that the noreturn bit is copied
  75    to the alias by verifying that calling the alias in a non-void
  76    function with no return statement isn't diagnosed.  */
  77
  78 extern _Noreturn void fnoreturn (void);
  79
  80 extern __typeof (fnoreturn)
  81   ATTR (visibility ("hidden"))
  82   fnoreturn __asm__ ("fnoreturn_name");
  83
  84 void fnoreturn (void)
  85 {
  86   __builtin_abort ();
  87 }
  88
  89 extern __typeof (fnoreturn)
  90   ATTR (alias ("fnoreturn_name"), copy (fnoreturn))
  91   fnoreturn_alias;
  92
  93 int call_fnoreturn_alias (void)
  94 {
  95   fnoreturn_alias ();
  96 }