re PR c/51360 (spurious unused-but-set-variable warning for var used in OpenMP pragma)

	PR c/51360
	* c-parser.c (c_parser_omp_clause_num_threads,
	c_parser_omp_clause_schedule): Call mark_exp_read.

	* semantics.c (finish_omp_clauses): For OMP_CLAUSE_NUM_THREADS_EXPR
	and OMP_CLAUSE_SCHEDULE_CHUNK_EXPR call mark_rvalue_use.

	* c-c++-common/gomp/pr51360.c: New test.
	* g++.dg/gomp/pr51360.C: New test.

From-SVN: r182381

gcc/ChangeLog

+2011-12-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/51360
+	* c-parser.c (c_parser_omp_clause_num_threads,
+	c_parser_omp_clause_schedule): Call mark_exp_read.
+
 2011-12-15  Romain Geissler  <romain.geissler@gmail.com>
 
 	* builtins.def (BUILT_IN_STPNCPY_CHK): New definition.

gcc/c-parser.c

@@ -9011,6 +9011,7 @@ c_parser_omp_clause_num_threads (c_parser *parser, tree list)
     {
       location_t expr_loc = c_parser_peek_token (parser)->location;
       tree c, t = c_parser_expression (parser).value;
+      mark_exp_read (t);
       t = c_fully_fold (t, false, NULL);
 
       c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, "expected %<)%>");
@@ -9218,6 +9219,7 @@ c_parser_omp_clause_schedule (c_parser *parser, tree list)
 
       here = c_parser_peek_token (parser)->location;
       t = c_parser_expr_no_commas (parser, NULL).value;
+      mark_exp_read (t);
       t = c_fully_fold (t, false, NULL);
 
       if (OMP_CLAUSE_SCHEDULE_KIND (c) == OMP_CLAUSE_SCHEDULE_RUNTIME)

gcc/cp/ChangeLog

+2011-12-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/51360
+	* semantics.c (finish_omp_clauses): For OMP_CLAUSE_NUM_THREADS_EXPR
+	and OMP_CLAUSE_SCHEDULE_CHUNK_EXPR call mark_rvalue_use.
+
 2011-12-15  Dodji Seketeli  <dodji@redhat.com>
 
 	PR c++/51473

gcc/cp/semantics.c

@@ -4087,6 +4087,8 @@ finish_omp_clauses (tree clauses)
 	      error ("num_threads expression must be integral");
 	      remove = true;
 	    }
+	  else
+	    OMP_CLAUSE_NUM_THREADS_EXPR (c) = mark_rvalue_use (t);
 	  break;
 
 	case OMP_CLAUSE_SCHEDULE:
@@ -4101,6 +4103,8 @@ finish_omp_clauses (tree clauses)
 	      error ("schedule chunk size expression must be integral");
 	      remove = true;
 	    }
+	  else
+	    OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = mark_rvalue_use (t);
 	  break;
 
 	case OMP_CLAUSE_NOWAIT:

gcc/testsuite/ChangeLog

 2011-12-15  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c/51360
+	* c-c++-common/gomp/pr51360.c: New test.
+	* g++.dg/gomp/pr51360.C: New test.
+
 	PR middle-end/49806
 	* gcc.dg/tree-ssa-vrp47.c: Add -fdump-tree-dom2 to dg-options.
 	Check for x_? & y in dom2 dump and xfail the check in dom1 dump.

gcc/testsuite/c-c++-common/gomp/pr51360.c

+/* PR c/51360 */
+/* { dg-do compile } */
+/* { dg-options "-Wunused -W -fopenmp" } */
+
+void
+foo (int a, int b, int c, int d)
+{
+  int m, n, o, p, i;
+  m = 6;
+  n = 1;
+  o = 5;
+  p = 1;
+  a = 6;
+  b = 1;
+  c = 5;
+  d = 1;
+  #pragma omp parallel for num_threads (m) if (n) schedule (static, o)
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp parallel for num_threads (a) if (b) schedule (static, c)
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp task final (p)
+    ;
+  #pragma omp task final (d)
+    ;
+}

gcc/testsuite/g++.dg/gomp/pr51360.C

+// PR c/51360
+// { dg-do compile }
+// { dg-options "-Wunused -W -fopenmp" }
+
+template <typename T>
+void
+foo (T a, T b, T c, T d)
+{
+  T m, n, o, p, i;
+  m = 6;
+  n = 1;
+  o = 5;
+  p = 1;
+  a = 6;
+  b = 1;
+  c = 5;
+  d = 1;
+  #pragma omp parallel for num_threads (m) if (n) schedule (static, o)
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp parallel for num_threads (a) if (b) schedule (static, c)
+  for (i = 0; i < 10; i++)
+    ;
+  #pragma omp task final (p)
+    ;
+  #pragma omp task final (d)
+    ;
+}
+
+void
+bar ()
+{
+  foo (0, 0, 0, 0);
+}