gcc/testsuite/gcc.dg/c99-const-expr-12.c

   1 /* Test for constant expressions: VLA size constraints.  */
   2 /* Origin: Joseph Myers <joseph@codesourcery.com> */
   3 /* { dg-do compile } */
   4 /* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
   5
   6 void
   7 f (int m)
   8 {
   9   /* An array size that is a constant expression, not just an integer
  10      constant expression, must be checked for being positive, but only
  11      an integer constant expression makes it not a VLA (which affects
  12      certain compatibility checks, in particular).  */
  13   int a1[0]; /* { dg-error "zero" } */
  14   int a2[-1]; /* { dg-error "negative" } */
  15   int a3[(int)(double)0.0]; /* { dg-error "zero" } */
  16   int a4[(int)-1.0]; /* { dg-error "negative" } */
  17   int a5[(int)+1.0];
  18   int a6[(int)+2.0];
  19   void *p = (m ? &a5 : &a6);
  20   int a7[(int)1.0];
  21   int a8[(int)2.0];
  22   void *q = (m ? &a7 : &a8); /* { dg-error "pointer type mismatch in conditional expression" } */
  23 }