On Wed, 4 Apr 2012, Tristan Gingold wrote:

> Hi,
> 
> this patch fixes a build time failure on VMS (while compiling Ada RTS file i-cstrin.adb) due to the use of short pointers:
> 
> i-cstrin.adb: In function 'Interfaces.C.Strings.To_Chars_Ptr':
> i-cstrin.adb:236:8: error: unrecognizable insn:
> (insn 80 79 81 13 (set (reg:SI 384)
>         (const_int 4294967288 [0xfffffff8])) i-cstrin.adb:234 -1
>      (nil))
> +===========================GNAT BUG DETECTED==============================+
> | Pro 7.1.0w (20120403-47) (ia64-hp-openvms) GCC error:                    |
> | in extract_insn, at recog.c:2123                                         |
> | Error detected around i-cstrin.adb:236:8                                 |
> 
> 
> Expansion of POINTER_PLUS_EXPR doesn't handle the case of PRECISION(sizetype) > PRECISION(type), leading to RTL expressions with different modes.
> 
> This patch fixes the build issue, tested on ia64-hp-openvms.
> Also tested with our internal testsuite.
> I haven't run the GCC testsuite on a regular platform, as the condition will never trigger.
> 
> Ok for trunk ?

Ok if you add a comment why this is needed.

Richard.

> Tristan.
> 
> 2012-04-04  Tristan Gingold  <gingold@adacore.com>
> 
> 	* expr.c (expand_expr_real_2): Handle larger sizetype in
> 	POINTER_PLUS_EXPR.
> 
> --- a/gcc/expr.c
> +++ b/gcc/expr.c
> @@ -7957,6 +7957,9 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_m
>         treeop1 = fold_convert_loc (loc, type,
>                                     fold_convert_loc (loc, ssizetype,
>                                                       treeop1));
> +      else if (TYPE_PRECISION (sizetype) > TYPE_PRECISION (type))
> +       treeop1 = fold_convert_loc (loc, type, treeop1);
> +
>      case PLUS_EXPR:
>        /* If we are adding a constant, a VAR_DECL that is sp, fp, or ap, and
>          something else, make sure we add the register to the constant and
> u
> 
> 
> 

-- 
Richard Guenther <rguenther@suse.de>
SUSE / SUSE Labs
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