diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e744b9fabc5..0826135faac 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,10 +1,15 @@
+2007-04-24  Ian Lance Taylor  <iant@google.com>
+
+	* flow.c (elim_reg_cond): Handle a comparison of a subreg.
+
 2007-04-24  Simon Martin  <simartin@users.sourceforge.net>
 
 	PR diagnostic/25923
 	* tree-pass.h (TDF_DIAGNOSTIC): New dump control to specify that a
 	diagnostic message is being built.
-	* tree-pretty-print.c (dump_generic_node): Only write the formatted text
-	into BUFFER's stream if we are not building a diagnostic message.
+	* tree-pretty-print.c (dump_generic_node): Only write the
+	formatted text into BUFFER's stream if we are not building a
+	diagnostic message.
 	* toplev.c (default_tree_printer): Pass TDF_DIAGNOSTIC to
 	dump_generic_node.
 	* Makefile.in (toplev.o): Depend on tree-pass.h.
diff --git a/gcc/flow.c b/gcc/flow.c
index 78c23281c6b..5b0249bec97 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -3437,7 +3437,13 @@ elim_reg_cond (rtx x, unsigned int regno)
 
   if (COMPARISON_P (x))
     {
-      if (REGNO (XEXP (x, 0)) == regno)
+      rtx reg;
+
+      reg = XEXP (x, 0);
+      if (GET_CODE (reg) == SUBREG)
+	reg = SUBREG_REG (reg);
+      gcc_assert (REG_P (reg));
+      if (REGNO (reg) == regno)
 	return const0_rtx;
       return x;
     }