c-decl.c (warn_missing_noreturn): Remove.

        * c-decl.c (warn_missing_noreturn): Remove.
        (c_expand_body): Don't set or check can_reach_end.
        * c-tree.h (warn_missing_noreturn): Move ...
        * flags.h: ... here.
        (can_reach_end): Remove.
        * flow.c (check_function_return_warnings): New.
        (make_edges): No edge to exit for noreturn sibcalls.
        * function.c (expand_function_end): Save the return value
        clobber instruction.
        (mark_function_status): Mark it.
        * function.h (struct function): Add x_clobber_return_insn.
        * jump.c (can_reach_end): Remove.
        (calculate_can_reach_end): Remove.
        (jump_optimize_1): Don't call it.
        * output.h (check_function_return_warnings): Declare.
        * toplev.c (warn_missing_noreturn): Move from c-decl.c
        (rest_of_compilation): Call check_function_return_warnings.

From-SVN: r36750

1 files changed, 3 insertions, 24 deletions

diff --git a/gcc/c-decl.c b/gcc/c-decl.c
index 940d4b1..9dbaa28 100644
--- a/gcc/c-decl.c
+++ b/gcc/c-decl.c
@@ -403,10 +403,6 @@ int warn_cast_qual;
 
 int warn_bad_function_cast;
 
-/* Warn about functions which might be candidates for attribute noreturn.  */
-
-int warn_missing_noreturn;
-
 /* Warn about traditional constructs whose meanings changed in ANSI C.  */
 
 int warn_traditional;
@@ -6760,9 +6756,6 @@ c_expand_body (fndecl, nested_p)
   /* Generate rtl for function exit.  */
   expand_function_end (input_filename, lineno, 0);
 
-  /* So we can tell if jump_optimize sets it to 1.  */
-  can_reach_end = 0;
-
   /* If this is a nested function, protect the local variables in the stack
      above us from being collected while we're compiling this function.  */
   if (nested_p)
@@ -6775,25 +6768,11 @@ c_expand_body (fndecl, nested_p)
   if (nested_p)
     ggc_pop_context ();
 
-  current_function_returns_null |= can_reach_end;
-
-  if (warn_missing_noreturn
-      && !TREE_THIS_VOLATILE (fndecl)
-      && !current_function_returns_null
-      && !current_function_returns_value)
-    warning ("function might be possible candidate for attribute `noreturn'");
-
-  if (TREE_THIS_VOLATILE (fndecl) && current_function_returns_null)
-    warning ("`noreturn' function does return");
-  else if (warn_return_type && can_reach_end
-	   && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fndecl))))
-    /* If this function returns non-void and control can drop through,
-       complain.  */
-    warning ("control reaches end of non-void function");
   /* With just -W, complain only if function returns both with
      and without a value.  */
-  else if (extra_warnings
-	   && current_function_returns_value && current_function_returns_null)
+  if (extra_warnings
+      && current_function_returns_value
+      && current_function_returns_null)
     warning ("this function may return with or without a value");
 
   /* If requested, warn about function definitions where the function will