TREE_ADDRESSABLE comment says "In a FUNCTION_DECL, nonzero means its
address is needed". However, as I point out in
http://gcc.gnu.org/ml/gcc-patches/2011-02/msg01525.html, this flag
gets set when making normal calls. It wasn't always like this.
gcc-4.0 was careful to not set TREE_ADDRESSABLE on FUNCTION_DECLs in
build_function_call, a feature lost in revision 100984. I'd like to
have that feature back for the above patch. Bootstrapped and
regression tested powerpc-linux. OK for 4.6?
* c-typeck.c (build_function_call_vec): Avoid setting TREE_ADDRESSABLE
on normal function calls.
Index: gcc/c-typeck.c
===================================================================
--- gcc/c-typeck.c (revision 170607)
+++ gcc/c-typeck.c (working copy)
@@ -2715,7 +2715,20 @@ build_function_call_vec (location_t loc,
fundecl = function;
}
if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
- function = function_to_pointer_conversion (loc, function);
+ {
+ if (fundecl)
+ {
+ /* Don't set TREE_ADDRESSABLE for the implicit function
+ pointer conversion in a function call. This allows
+ TREE_ADDRESSABLE to be used to detect explicit function
+ address operations. */
+ bool addressable = TREE_ADDRESSABLE (fundecl);
+ function = function_to_pointer_conversion (loc, function);
+ TREE_ADDRESSABLE (fundecl) = addressable;
+ }
+ else
+ function = function_to_pointer_conversion (loc, function);
+ }
/* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
expressions, like those used for ObjC messenger dispatches. */
--
Alan Modra
Australia Development Lab, IBM
