--- gcc/cfgexpand.c.jj	2010-06-20 17:13:36.000000000 +0200
+++ gcc/cfgexpand.c	2010-07-20 11:21:17.000000000 +0200
@@ -2164,7 +2164,7 @@ expand_debug_expr (tree exp)
 	  op0 = simplify_gen_subreg (mode, op0, inner_mode,
 				     subreg_lowpart_offset (mode,
 							    inner_mode));
-	else if (unsignedp)
+	else if (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0))))
 	  op0 = gen_rtx_ZERO_EXTEND (mode, op0);
 	else
 	  op0 = gen_rtx_SIGN_EXTEND (mode, op0);
--- gcc/testsuite/gcc.dg/guality/pr45003-1.c.jj	2010-07-20 13:56:34.000000000 +0200
+++ gcc/testsuite/gcc.dg/guality/pr45003-1.c	2010-07-20 13:58:38.000000000 +0200
@@ -0,0 +1,31 @@
+/* PR debug/45003 */
+/* { dg-do run { target { x86_64-*-* && lp64 } } } */
+/* { dg-options "-g" } */
+
+int __attribute__((noinline))
+foo (unsigned short *p)
+{
+  int a = *p;
+  asm volatile ("nop");
+  asm volatile ("nop" : : "D" (a));	/* { dg-final { gdb-test 10 "a" "0x8078" } } */
+  return 0;
+}
+
+int __attribute__((noinline))
+bar (short *p)
+{
+  unsigned int a = *p;
+  asm volatile ("nop");
+  asm volatile ("nop" : : "D" (a));	/* { dg-final { gdb-test 19 "a" "0xffff8078" } } */
+  return 0;
+}
+
+int
+main ()
+{
+  unsigned short us = 0x8078;
+  foo (&us);
+  short s = -32648;
+  bar (&s);
+  return 0;
+}