1 files changed, 1 insertions, 1 deletions
diff --git a/expand.c b/expand.c
index c7f7b58..b679a90 100644
--- a/expand.c
+++ b/expand.c
@@ -367,7 +367,7 @@ variable_expand_string (line, string, length)
 	  break;
 
 	default:
-	  if (isblank (p[-1]))
+	  if (isblank ((unsigned char)p[-1]))
 	    break;
 
 	  /* A $ followed by a random char is a variable reference: