c-parser.c (c_parser_omp_clause_schedule): Warn if OMP_CLAUSE_SCHEDULE_CHUNK_EXPR is known not to be positive.

	* c-parser.c (c_parser_omp_clause_schedule): Warn if
	OMP_CLAUSE_SCHEDULE_CHUNK_EXPR is known not to be positive.

	* semantics.c (finish_omp_clauses) <case OMP_CLAUSE_SCHEDULE>: Warn
	if OMP_CLAUSE_SCHEDULE_CHUNK_EXPR is known not to be positive.

	* openmp.c (resolve_omp_clauses): Warn if chunk_size is known not to
	be positive.

	* c-c++-common/gomp/schedule-1.c: New test.
	* gfortran.dg/gomp/schedule-1.f90: New test.

	* testsuite/libgomp.c/doacross-1.c (main): Use schedule(static)
	instead of invalid schedule(static, 0).
	* testsuite/libgomp.c/doacross-2.c (main): Likewise.

From-SVN: r236793

9 files changed, 75 insertions, 1 deletions

diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index f3bb0e9..f7d1a6d 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,8 @@
+2016-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* c-parser.c (c_parser_omp_clause_schedule): Warn if
+	OMP_CLAUSE_SCHEDULE_CHUNK_EXPR is known not to be positive.
+
 2016-05-25  Marek Polacek  <polacek@redhat.com>
 
 	PR c/71265
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 1cf4fb4..fda2df8 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -12128,7 +12128,20 @@ c_parser_omp_clause_schedule (c_parser *parser, tree list)
 		  "schedule %<auto%> does not take "
 		  "a %<chunk_size%> parameter");
       else if (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE)
-	OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t;
+	{
+	  /* Attempt to statically determine when the number isn't
+	     positive.  */
+	  tree s = fold_build2_loc (loc, LE_EXPR, boolean_type_node, t,
+				    build_int_cst (TREE_TYPE (t), 0));
+	  protected_set_expr_location (s, loc);
+	  if (s == boolean_true_node)
+	    {
+	      warning_at (loc, 0,
+			  "chunk size value must be positive");
+	      t = integer_one_node;
+	    }
+	  OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t;
+	}
       else
 	c_parser_error (parser, "expected integer expression");
 
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index ff5d8f4..770f817 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2016-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* semantics.c (finish_omp_clauses) <case OMP_CLAUSE_SCHEDULE>: Warn
+	if OMP_CLAUSE_SCHEDULE_CHUNK_EXPR is known not to be positive.
+
 2016-05-26  Patrick Palka  <ppalka@gcc.gnu.org>
 
 	PR c++/70822
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 0cef867..253d31a 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -6319,6 +6319,17 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
 			  break;
 			}
 		    }
+		  else
+		    {
+		      t = maybe_constant_value (t);
+		      if (TREE_CODE (t) == INTEGER_CST
+			  && tree_int_cst_sgn (t) != 1)
+			{
+			  warning_at (OMP_CLAUSE_LOCATION (c), 0,
+				      "chunk size value must be positive");
+			  t = integer_one_node;
+			}
+		    }
 		  t = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
 		}
 	      OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t;
diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 8db7017..73235c6 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,8 @@
+2016-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* openmp.c (resolve_omp_clauses): Warn if chunk_size is known not to
+	be positive.
+
 2016-05-23  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
 
 	PR fortran/66461
diff --git a/gcc/fortran/openmp.c b/gcc/fortran/openmp.c
index 1481719..2689d30 100644
--- a/gcc/fortran/openmp.c
+++ b/gcc/fortran/openmp.c
@@ -3259,6 +3259,11 @@ resolve_omp_clauses (gfc_code *code, gfc_omp_clauses *omp_clauses,
 	  || expr->ts.type != BT_INTEGER || expr->rank != 0)
 	gfc_error ("SCHEDULE clause's chunk_size at %L requires "
 		   "a scalar INTEGER expression", &expr->where);
+      else if (expr->expr_type == EXPR_CONSTANT
+	       && expr->ts.type == BT_INTEGER
+	       && mpz_sgn (expr->value.integer) <= 0)
+	gfc_warning (0, "INTEGER expression of SCHEDULE clause's chunk_size "
+		     "at %L must be positive", &expr->where);
     }
 
   /* Check that no symbol appears on multiple clauses, except that
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9624212..f2a7a56 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-05-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* c-c++-common/gomp/schedule-1.c: New test.
+	* gfortran.dg/gomp/schedule-1.f90: New test.
+
 2016-05-26  Patrick Palka  <ppalka@gcc.gnu.org>
 
 	PR c++/70822
diff --git a/gcc/testsuite/c-c++-common/gomp/schedule-1.c b/gcc/testsuite/c-c++-common/gomp/schedule-1.c
new file mode 100644
index 0000000..8700ff6
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/gomp/schedule-1.c
@@ -0,0 +1,14 @@
+void
+foo (void)
+{
+  int i;
+  #pragma omp for schedule(static, 1)
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp for schedule(static, 0)		/* { dg-warning "chunk size value must be positive" } */
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp for schedule(static, -7)		/* { dg-warning "chunk size value must be positive" } */
+  for (i = 0; i < 10; i++)
+    ;
+}
diff --git a/gcc/testsuite/gfortran.dg/gomp/schedule-1.f90 b/gcc/testsuite/gfortran.dg/gomp/schedule-1.f90
new file mode 100644
index 0000000..3d64294
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/gomp/schedule-1.f90
@@ -0,0 +1,11 @@
+  integer :: i
+  !$omp do schedule(static, 1)
+  do i = 1, 10
+  end do
+  !$omp do schedule(static, 0)	! { dg-warning "must be positive" }
+  do i = 1, 10
+  end do
+  !$omp do schedule(static, -7)	! { dg-warning "must be positive" }
+  do i = 1, 10
+  end do
+end