diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 35a872893bb..790bc10edb2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2002-02-10  Richard Henderson  <rth@redhat.com>
+
+	PR c/5623
+	* c-typeck.c (incomplete_type_error): Handle flexible array members.
+
 2002-02-10  Richard Henderson  <rth@redhat.com>
 
 	PR c++/5624
diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index dc844bfb7a3..5d5b5f97870 100644
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -149,6 +149,11 @@ incomplete_type_error (value, type)
 	case ARRAY_TYPE:
 	  if (TYPE_DOMAIN (type))
 	    {
+	      if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
+		{
+		  error ("invalid use of flexible array member");
+		  return;
+		}
 	      type = TREE_TYPE (type);
 	      goto retry;
 	    }