gcc/testsuite/gcc.dg/const-elim-1.c

   1 /* Verify that constants in memory, referenced only by dead code,
   2    are not emitted to the object file.
   3    FIXME: Not presently possible to apply -pedantic to code with
   4    complex constants in it.  The __extension__ should shut up the
   5    warning but doesn't.  (Hard to fix -- the lexer is not aware of
   6    the parser's state.)  */
   7
   8 /* { dg-do compile } */
   9 /* { dg-options "-O2 -std=c99" } */
  10 /* { dg-final { scan-assembler-not "L\\\$?C\[^A-Z\]" } } */
  11
  12 #define I (__extension__ 1.0iF)
  13
  14 struct S { int a; double b[2]; void *c; };
  15
  16 extern void use_str(const char *);
  17 extern void use_S(const struct S *);
  18 extern void use_cplx(__complex__ double);
  19
  20 static inline int
  21 returns_23(void) { return 23; }
  22
  23 void
  24 test1(void)
  25 {
  26         if (returns_23() == 23)
  27                 return;
  28
  29         use_str("waltz, nymph, for quick jigs vex bud");
  30         use_S(&(const struct S){12, {3.1415, 2.1828}, 0 });
  31         use_cplx(3.1415 + 2.1828*I);
  32 }
  33
  34 void
  35 test2(void)
  36 {
  37         const char *str = "pack my box with five dozen liquor jugs";
  38         const struct S S = { 23, { 1.414, 1.618 }, 0 };
  39         const __complex__ double cplx = 1.414 + 1.618*I;
  40
  41         if (returns_23() == 23)
  42                 return;
  43
  44         use_str(str);
  45         use_S(&S);
  46         use_cplx(cplx);
  47 }
  48