re PR c/66322 (Linus Torvalds: -Wswitch-bool produces dubious warnings, fails to notice really bad things)

	PR c/66322
	* c-common.c (check_case_bounds): Add bool * parameter.  Set
	OUTSIDE_RANGE_P.
	(c_add_case_label): Add bool * parameter.  Pass it down to
	check_case_bounds.
	(c_do_switch_warnings): Add bool parameters.  Implement -Wswitch-bool
	warning here.
	* c-common.h (c_add_case_label, c_do_switch_warnings): Update
	declarations.

	* c-typeck.c (struct c_switch): Add BOOL_COND_P and OUTSIDE_RANGE_P.
	(c_start_case): Set BOOL_COND_P and OUTSIDE_RANGE_P.  Don't warn
	about -Wswitch-bool here.
	(do_case): Update c_add_case_label call.
	(c_finish_case): Update c_do_switch_warnings call.

	* decl.c (struct cp_switch): Add OUTSIDE_RANGE_P.
	(push_switch): Set OUTSIDE_RANGE_P.
	(pop_switch): Update c_do_switch_warnings call.
	(finish_case_label): Update c_add_case_label call.
	* semantics.c (finish_switch_cond): Don't warn about -Wswitch-bool
	here.

	* function.c (stack_protect_epilogue): Remove a cast to int.
	* doc/invoke.texi: Update -Wswitch-bool description.

	* c-c++-common/pr60439.c: Add dg-prune-output and add switch cases.
	* c-c++-common/pr66322.c: New test.
	* g++.dg/eh/scope1.C: Remove dg-warning.

From-SVN: r225116

3 files changed, 21 insertions, 7 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 4a3b2d8..c16b068 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,13 @@
+2015-06-29  Marek Polacek  <polacek@redhat.com>
+
+	PR c/66322
+	* decl.c (struct cp_switch): Add OUTSIDE_RANGE_P.
+	(push_switch): Set OUTSIDE_RANGE_P.
+	(pop_switch): Update c_do_switch_warnings call.
+	(finish_case_label): Update c_add_case_label call.
+	* semantics.c (finish_switch_cond): Don't warn about -Wswitch-bool
+	here.
+
 2015-06-27  Marek Polacek  <polacek@redhat.com>
 
 	* call.c: Use VECTOR_TYPE_P.
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 0683f26..498ed71 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -3208,6 +3208,9 @@ struct cp_switch
      label.  We need a tree, rather than simply a hash table, because
      of the GNU case range extension.  */
   splay_tree cases;
+  /* Remember whether there was a case value that is outside the
+     range of the original type of the controlling expression.  */
+  bool outside_range_p;
 };
 
 /* A stack of the currently active switch statements.  The innermost
@@ -3229,6 +3232,7 @@ push_switch (tree switch_stmt)
   p->next = switch_stack;
   p->switch_stmt = switch_stmt;
   p->cases = splay_tree_new (case_compare, NULL, NULL);
+  p->outside_range_p = false;
   switch_stack = p;
 }
 
@@ -3240,10 +3244,14 @@ pop_switch (void)
 
   /* Emit warnings as needed.  */
   switch_location = EXPR_LOC_OR_LOC (cs->switch_stmt, input_location);
+  const bool bool_cond_p
+    = (SWITCH_STMT_TYPE (cs->switch_stmt)
+       && TREE_CODE (SWITCH_STMT_TYPE (cs->switch_stmt)) == BOOLEAN_TYPE);
   if (!processing_template_decl)
     c_do_switch_warnings (cs->cases, switch_location,
 			  SWITCH_STMT_TYPE (cs->switch_stmt),
-			  SWITCH_STMT_COND (cs->switch_stmt));
+			  SWITCH_STMT_COND (cs->switch_stmt),
+			  bool_cond_p, cs->outside_range_p);
 
   splay_tree_delete (cs->cases);
   switch_stack = switch_stack->next;
@@ -3308,7 +3316,8 @@ finish_case_label (location_t loc, tree low_value, tree high_value)
   high_value = case_conversion (type, high_value);
 
   r = c_add_case_label (loc, switch_stack->cases, cond, type,
-			low_value, high_value);
+			low_value, high_value,
+			&switch_stack->outside_range_p);
 
   /* After labels, make any new cleanups in the function go into their
      own new (temporary) binding contour.  */
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 4b8ce3b..c23d9be 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -1156,11 +1156,6 @@ finish_switch_cond (tree cond, tree switch_stmt)
 	orig_type = TREE_TYPE (cond);
       if (cond != error_mark_node)
 	{
-	  /* Warn if the condition has boolean value.  */
-	  if (TREE_CODE (orig_type) == BOOLEAN_TYPE)
-	    warning_at (input_location, OPT_Wswitch_bool,
-			"switch condition has type bool");
-
 	  /* [stmt.switch]
 
 	     Integral promotions are performed.  */