From: Richard Kenner <kenner@gcc.gnu.org>
Date: Mon, 2 Oct 1995 01:23:04 +0000 (-0400)
Subject: (expand_expr, case COMPONENT_REF): If getting component of union of
X-Git-Tag: misc/cutover-egcs-0~3549
X-Git-Url: https://gcc.gnu.org/git/?a=commitdiff_plain;h=b74f5ff2bd0793d863acf42138a5547ee59dde51;p=gcc.git

(expand_expr, case COMPONENT_REF): If getting component of union of
variable size, propagate TARGET.

From-SVN: r10415
---

diff --git a/gcc/expr.c b/gcc/expr.c
index a1fda985b78f..d2de924b6aee 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -4762,8 +4762,18 @@ expand_expr (exp, target, tmode, modifier)
 
 	/* In some cases, we will be offsetting OP0's address by a constant.
 	   So get it as a sum, if possible.  If we will be using it
-	   directly in an insn, we validate it.  */
-	op0 = expand_expr (tem, NULL_RTX, VOIDmode, EXPAND_SUM);
+	   directly in an insn, we validate it. 
+
+	   If TEM's type is a union of variable size, pass TARGET to the inner
+	   computation, since it will need a temporary and TARGET is known
+	   to have to do.  This occurs in unchecked conversion in Ada.  */
+  
+	op0 = expand_expr (tem,
+			   (TREE_CODE (TREE_TYPE (tem)) == UNION_TYPE
+			    && (TREE_CODE (TYPE_SIZE (TREE_TYPE (tem)))
+				!= INTEGER_CST)
+			    ? target : NULL_RTX),
+			   VOIDmode, EXPAND_SUM);
 
 	/* If this is a constant, put it into a register if it is a
 	   legitimate constant and memory if it isn't.  */