walways-true-2.c

来自「用于进行gcc测试」· C语言 代码 · 共 61 行

// Make sure we don't assume that a weak symbol is always non-NULL.
// This is just like Walways-true-1.C, except that it uses a weak
// symbol.
// Origin: Ian Lance Taylor <[e-mail]>

// { dg-do compile}
// { dg-options "-Waddress" }
// { dg-require-weak "" }

extern int foo (int) __attribute__ ((weak));

int i __attribute__ ((weak));

void
bar (int a)
{
 lab:
  if (foo)
    foo (0);
  if (foo (1))
    ;
  if (&i)
    foo (2);
  if (i)
    foo (3);
  if (&a)	// { dg-warning "always evaluate as" "correct warning" }
    foo (4);
  if (a)
    foo (5);
  if (&&lab)	// { dg-warning "always evaluate as" "correct warning" }
    foo (6);
  if (foo == 0)
    foo (7);
  if (foo (1) == 0)
    foo (8);
  if (&i == 0)
    foo (9);
  if (i == 0)
    foo (10);
  if (&a == 0)	// { dg-warning "never be NULL" "correct warning" }
    foo (11);
  if (a == 0)
    foo (12);
  if (&&lab == 0) // { dg-warning "never be NULL" "correct warning" }
    foo (13);
  if (0 == foo)
    foo (14);
  if (0 == foo (1))
    foo (15);
  if (0 == &i)
    foo (16);
  if (0 == i)
    foo (17);
  if (0 == &a)	// { dg-warning "never be NULL" "correct warning" }
    foo (18);
  if (0 == a)
    foo (19);
  if (0 == &&lab) // { dg-warning "never be NULL" "correct warning" }
    foo (20);
}