diff --git a/ChangeLog b/ChangeLog
index 9cbb1e61..f046a0f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2012-01-29  Paul Smith  <psmith@gnu.org>
 
+	* gmk-default.scm (to-string-maybe): Variables map to empty strings.
+	In Guile 2.0, (define ...) results in a variable object so make
+	sure that maps to an empty string in make.
+
 	* variable.c (parse_variable_definition): New POSIX assignment ::=
 	Take a struct variable to return more information after parsing.
 	(assign_variable_definition): New parse_variable_definition() call.
diff --git a/gmk-default.scm b/gmk-default.scm
index 9aca54a5..4dabe25d 100644
--- a/gmk-default.scm
+++ b/gmk-default.scm
@@ -20,6 +20,7 @@
    ;; In GNU make, "false" is the empty string
    ((or (not x)
         (unspecified? x)
+        (variable? x)
         (null? x)
         (and (string? x) (string-null? x)))
     #f)