diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2ff2414d9e7..cf5369d3a31 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2003-08-20  Roger Sayle  <roger@eyesopen.com>
+
+	PR middle-end/11984
+	* fold-const.c (fold <PLUS_EXPR>): Check for integer constant
+	operands before calling tree_int_cst_lt when performing associative
+	transformations.
+
 2003-08-20  Jason Merrill  <jason@redhat.com>
 
 	* tree.h (IS_EXPR_CODE_CLASS): Also include 'r' and 's'.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index ef7c086087b..bf6b1f8e9f1 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -5884,7 +5884,9 @@ fold (tree expr)
 		 example: ((X*2 + 4) - 8U)/2.  */
 	      if (minus_lit0 && lit0)
 		{
-		  if (tree_int_cst_lt (lit0, minus_lit0))
+		  if (TREE_CODE (lit0) == INTEGER_CST
+		      && TREE_CODE (minus_lit0) == INTEGER_CST
+		      && tree_int_cst_lt (lit0, minus_lit0))
 		    {
 		      minus_lit0 = associate_trees (minus_lit0, lit0,
 						    MINUS_EXPR, type);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bbbf552c530..869e26edf57 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2003-08-20  Roger Sayle  <roger@eyesopen.com>
+
+	PR middle-end/11984
+	* gcc.dg/20030820-1.c: New test case.
+
 2003-08-20  Nathan Sidwell  <nathan@codesourcery.com>
 
 	PR c++/11945
diff --git a/gcc/testsuite/gcc.dg/20030820-1.c b/gcc/testsuite/gcc.dg/20030820-1.c
new file mode 100644
index 00000000000..f86fb3978f4
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/20030820-1.c
@@ -0,0 +1,13 @@
+/* PR middle-end/11984 */
+/* The following program used to ICE in fold because we didn't check
+   whether the constants we were reassociating were integer constants
+   before calling tree_int_cst_lt.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -ffast-math" } */
+
+double f(double x)
+{
+  return 1.0 - x - 0.1;
+}
+