Fix ICE on unaligned assignment of return value

[Eric Botcazou]

This is a regression present on mainline and 4.9 branch and visible e.g. on 
SPARC64: the code dealing with values returned in PARALLEL fails to handle the 
case of an unaligned target if the mode is an integral mode and not BLKmode.

Tested on SPARC64/Solaris and x86-64/Linux, applied on mainline and 4.9 branch 
as obvious.


2014-07-20  Eric Botcazou  <ebotca...@adacore.com>

        * expr.c (store_field): Handle VOIDmode for calls that return values
        in multiple locations.


2014-07-20  Eric Botcazou  <ebotca...@adacore.com>

        * gnat.dg/pack20.ad[sb]: New test.
        * gnat.dg/pack20_pkg.ads: New helper.


-- 
Eric Botcazou
Index: expr.c
===================================================================
--- expr.c	(revision 212833)
+++ expr.c	(working copy)
@@ -6581,7 +6581,7 @@ store_field (rtx target, HOST_WIDE_INT b
 	{
 	  HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (exp));
 	  rtx temp_target;
-	  if (mode == BLKmode)
+	  if (mode == BLKmode || mode == VOIDmode)
 	    mode = smallest_mode_for_size (size * BITS_PER_UNIT, MODE_INT);
 	  temp_target = gen_reg_rtx (mode);
 	  emit_group_store (temp_target, temp, TREE_TYPE (exp), size);
package body Pack20 is

   procedure Proc (A : Rec) is
      Local : Rec := A;
   begin
      Modify (Local.Fixed);
   end;

end Pack20;
-- { dg-do compile }

with Pack20_Pkg; use Pack20_Pkg;

package Pack20 is

   type Rec is record
      Simple_Type  : Integer;
      Fixed        : String_Ptr;
   end record;
   pragma Pack (Rec);

   procedure Proc (A : Rec);

end Pack20;
package Pack20_Pkg is

   type String_Ptr is access all String;

   procedure Modify (Fixed : in out String_Ptr);

end Pack20_Pkg;