From patchwork Wed Mar 30 16:19:01 2011
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Subject: A small patch to fix an arm bootstrap failure
Date: Wed, 30 Mar 2011 06:19:01 -0000
From: Vladimir Makarov <vmakarov@redhat.com>
X-Patchwork-Id: 88937
Message-Id: <4D9357F5.7080105@redhat.com>
To: gcc-patches <gcc-patches@gcc.gnu.org>

The following patch is to fix an arm bootstrap failure described in

http://gcc.gnu.org/ml/gcc/2011-03/msg00499.html

when variable mode is set but not used because it is used when macro 
HONOR_REG_ALLOC_ORDER is defined.

I found that 2 variables mode in different scopes is defined in function 
assign_hard_reg.  Using only one variable will guarantee usage of the 
variable.

The patch has been committed as obvious after successful bootstrap on 
x86_64.


2011-03-30  Vladimir Makarov <vmakarov@redhat.com>

         * ira-color.c (ira_assign_hard_reg): Use only one variable 'mode'.


Index: ira-color.c
===================================================================
--- ira-color.c	(revision 171713)
+++ ira-color.c	(working copy)
@@ -1622,10 +1622,11 @@ assign_hard_reg (ira_allocno_t a, bool r
 	      if (hard_regno >= 0
 		  && ira_class_hard_reg_index[aclass][hard_regno] >= 0)
 		{
-		  enum machine_mode mode = ALLOCNO_MODE (conflict_a);
-		  int conflict_nregs = hard_regno_nregs[hard_regno][mode];
 		  int n_objects = ALLOCNO_NUM_OBJECTS (conflict_a);
+		  int conflict_nregs;
 
+		  mode = ALLOCNO_MODE (conflict_a);
+		  conflict_nregs = hard_regno_nregs[hard_regno][mode];
 		  if (conflict_nregs == n_objects && conflict_nregs > 1)
 		    {
 		      int num = OBJECT_SUBWORD (conflict_obj);