diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 0b4e5a84db9..beb0b8125f0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+Tue Dec 15 11:55:30 1998  Nick Clifton  <nickc@cygnus.com>
+
+	* integrate.c (copy_rtx_and_substitute): If a SUBREG is
+	replaced by a CONCAT whoes components do not have the same
+	mode as the original SUBREG, use a new SUBREG to restore the
+	mode. 
+
+	* emit-rtl.c (subreg_realpart_p): Cope with subregs containing
+	multiword complex values.
+
 1998-12-15  Zack Weinberg  <zack@rabi.phys.columbia.edu>
 
 	* cppalloc.c: Add xstrdup here.
diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c
index c5d5060680e..701415f2c0f 100644
--- a/gcc/emit-rtl.c
+++ b/gcc/emit-rtl.c
@@ -942,7 +942,7 @@ subreg_realpart_p (x)
   if (GET_CODE (x) != SUBREG)
     abort ();
 
-  return SUBREG_WORD (x) == 0;
+  return SUBREG_WORD (x) * UNITS_PER_WORD < GET_MODE_UNIT_SIZE (GET_MODE (SUBREG_REG (x)));
 }
 
 /* Assuming that X is an rtx (e.g., MEM, REG or SUBREG) for a value,
diff --git a/gcc/integrate.c b/gcc/integrate.c
index 4c1464cb644..943eeaff0d9 100644
--- a/gcc/integrate.c
+++ b/gcc/integrate.c
@@ -2451,7 +2451,17 @@ copy_rtx_and_substitute (orig, map)
 	return gen_rtx_SUBREG (GET_MODE (orig), SUBREG_REG (copy),
 			       SUBREG_WORD (orig) + SUBREG_WORD (copy));
       else if (GET_CODE (copy) == CONCAT)
-	return (subreg_realpart_p (orig) ? XEXP (copy, 0) : XEXP (copy, 1));
+	{
+	  rtx retval = subreg_realpart_p (orig) ? XEXP (copy, 0) : XEXP (copy, 1);
+
+	  if (GET_MODE (retval) == GET_MODE (orig))
+	    return retval;
+	  else
+	    return gen_rtx_SUBREG (GET_MODE (orig), retval,
+				   (SUBREG_WORD (orig) %
+				    (GET_MODE_UNIT_SIZE (GET_MODE (SUBREG_REG (orig)))
+				     / (unsigned) UNITS_PER_WORD)));
+	}
       else
 	return gen_rtx_SUBREG (GET_MODE (orig), copy,
 			       SUBREG_WORD (orig));