On Thu, Mar 3, 2011 at 3:33 PM, Alan Modra <amo...@gmail.com> wrote:
> 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?
You'll get the addressable flag re-applied by the operand scanner.
Richard.
> * 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
>
