trunk/gcc/testsuite/gcc.dg/debug/vta-1.c

   1 /* https://bugzilla.redhat.com/show_bug.cgi?id=521991#c5
   2
   3    Distilled from Linux XFS source code.  foo, inlined into bar, ends
   4    up with debug stmts referencing the addressable variable b.
   5    Optimization made it non-addressable, and then completely optimized
   6    away, before we got a chance to rename (and discard) the occurrence
   7    in the debug stmt.  When we did, we crashed, attempting to rename
   8    an unreference variable.  */
   9
  10 /* { dg-do compile } */
  11
  12 static inline int
  13 foo (void *x, unsigned y)
  14 {
  15   unsigned z = *(unsigned long *) x % y;
  16   *(unsigned long *) x = *(unsigned long *) x / y;
  17   return z;
  18 }
  19
  20 struct S
  21 {
  22   unsigned t;
  23 };
  24
  25 void
  26 bar (struct S *x, int *y)
  27 {
  28   int a = 0;
  29   unsigned long b = x->t;
  30   foo (&b, x->t);
  31   for (;; a++)
  32     if (b)
  33       *y = 1;
  34 }