1 files changed, 57 insertions, 0 deletions

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 9f557b8..7085d5a 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -3426,6 +3426,13 @@ struct cp_switch
   /* Remember whether there was a case value that is outside the
      range of the original type of the controlling expression.  */
   bool outside_range_p;
+  /* Remember whether a default: case label has been seen.  */
+  bool has_default_p;
+  /* Remember whether a BREAK_STMT has been seen in this SWITCH_STMT.  */
+  bool break_stmt_seen_p;
+  /* Set if inside of {FOR,DO,WHILE}_BODY nested inside of a switch,
+     where BREAK_STMT doesn't belong to the SWITCH_STMT.  */
+  bool in_loop_body_p;
 };
 
 /* A stack of the currently active switch statements.  The innermost
@@ -3448,6 +3455,9 @@ push_switch (tree switch_stmt)
   p->switch_stmt = switch_stmt;
   p->cases = splay_tree_new (case_compare, NULL, NULL);
   p->outside_range_p = false;
+  p->has_default_p = false;
+  p->break_stmt_seen_p = false;
+  p->in_loop_body_p = false;
   switch_stack = p;
 }
 
@@ -3468,11 +3478,55 @@ pop_switch (void)
 			  SWITCH_STMT_COND (cs->switch_stmt),
 			  bool_cond_p, cs->outside_range_p);
 
+  /* For the benefit of block_may_fallthru remember if the switch body
+     case labels cover all possible values and if there are break; stmts.  */
+  if (cs->has_default_p
+      || (!processing_template_decl
+	  && c_switch_covers_all_cases_p (cs->cases,
+					  SWITCH_STMT_TYPE (cs->switch_stmt))))
+    SWITCH_STMT_ALL_CASES_P (cs->switch_stmt) = 1;
+  if (!cs->break_stmt_seen_p)
+    SWITCH_STMT_NO_BREAK_P (cs->switch_stmt) = 1;
+  gcc_assert (!cs->in_loop_body_p);
   splay_tree_delete (cs->cases);
   switch_stack = switch_stack->next;
   free (cs);
 }
 
+/* Note that a BREAK_STMT is about to be added.  If it is inside of
+   a SWITCH_STMT and not inside of a loop body inside of it, note
+   in switch_stack we've seen a BREAK_STMT.  */
+
+void
+note_break_stmt (void)
+{
+  if (switch_stack && !switch_stack->in_loop_body_p)
+    switch_stack->break_stmt_seen_p = true;
+}
+
+/* Note the start of processing of an iteration statement's body.
+   The note_break_stmt function will do nothing while processing it.
+   Return a flag that should be passed to note_iteration_stmt_body_end.  */
+
+bool
+note_iteration_stmt_body_start (void)
+{
+  if (!switch_stack)
+    return false;
+  bool ret = switch_stack->in_loop_body_p;
+  switch_stack->in_loop_body_p = true;
+  return ret;
+}
+
+/* Note the end of processing of an iteration statement's body.  */
+
+void
+note_iteration_stmt_body_end (bool prev)
+{
+  if (switch_stack)
+    switch_stack->in_loop_body_p = prev;
+}
+
 /* Convert a case constant VALUE in a switch to the type TYPE of the switch
    condition.  Note that if TYPE and VALUE are already integral we don't
    really do the conversion because the language-independent
@@ -3507,6 +3561,9 @@ finish_case_label (location_t loc, tree low_value, tree high_value)
   cp_binding_level *p;
   tree type;
 
+  if (low_value == NULL_TREE && high_value == NULL_TREE)
+    switch_stack->has_default_p = true;
+
   if (processing_template_decl)
     {
       tree label;