Make def:<var> compatible between "static" and "dynamic" vars.

[exim.git] / src / src / expand.c

diff --git a/src/src/expand.c b/src/src/expand.c
index 2c29c26d538550801ae7574e597b588860e17fd0..26f7f10acfed2bb61ba423c60014927410ef2af5 100644 (file)
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -2066,7 +2066,8 @@ switch (vp->type)
   case vtype_string_func:
     {
     stringptr_fn_t * fn = (stringptr_fn_t *) val;
-    return fn();
+    uschar* s = fn();
+    return s ? s : US"";
     }
 
   case vtype_pspace: