gcc/testsuite/c-c++-common/gomp/imperfect-attributes.c

/* { dg-do compile { target { c || c++11 } } } */

/* Check that a nested FOR loop with standard c/c++ attributes on it 
   (not the C++ attribute syntax for OpenMP directives)
   gives an error.  */

extern void do_something (void);


/* This one should be OK, an empty attribute list is ignored in both C
   and C++.  */
void imperfect1 (int x, int y)
{
#pragma omp for collapse (2)
  for (int i = 0; i < x; i++)
    {
      [[]] for (int j = 0; j < y; j++)
	do_something ();
    }
}

void perfect1 (int x, int y)
{
#pragma omp for ordered (2)
  for (int i = 0; i < x; i++)
    {
      [[]] for (int j = 0; j < y; j++)
	do_something ();
    }
}

/* Similar, but put the attributes on a block wrapping the nested loop
   instead.  This is not allowed by the grammar.  */

void imperfect2 (int x, int y)
{
#pragma omp for collapse (2)
  for (int i = 0; i < x; i++)  /* { dg-error "not enough nested loops" } */
    {
    [[]]
      {
	for (int j = 0; j < y; j++)  /* { dg-error "loop not permitted in intervening code" } */
	  do_something ();
      }
    }
}

void perfect2 (int x, int y)
{
#pragma omp for ordered (2)
  for (int i = 0; i < x; i++)  /* { dg-error "not enough nested loops" } */
    /* { dg-error "inner loops must be perfectly nested" "" { target *-*-*} .-1 } */
    {
    [[]]
      {
	for (int j = 0; j < y; j++)  /* { dg-error "loop not permitted in intervening code" } */
	  do_something ();
      }
    }
}

/* Make sure attributes are accepted in the innermost loop body, which has
   no intervening code restrictions.  */

void imperfect3 (int x, int y)
{
#pragma omp for collapse (2)
  for (int i = 0; i < x; i++)
    for (int j = 0; j < y; j++)
      {
	[[]] do_something ();
      }
}

void perfect3 (int x, int y)
{
#pragma omp for ordered (2)
  for (int i = 0; i < x; i++)
      for (int j = 0; j < y; j++)
	{
	  [[]] do_something ();
	}
}