2 files changed, 14 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index f5b1a073f..bebc97b53 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-09-28  Barton E. Schaefer  <schaefer@zsh.org>
+
+	* 36669: Src/lex.c: fix ${(z)...} of an an incomplete math
+	expression by restoring "((" at the front of the token
+
 2015-09-28  Daniel Shahaf  <d.s@daniel.shahaf.name>
 
 	* unposted: Etc/zsh-development-guide: Update link to my
diff --git a/Src/lex.c b/Src/lex.c
index 70f3d142a..89af96123 100644
--- a/Src/lex.c
+++ b/Src/lex.c
@@ -783,6 +783,15 @@ gettok(void)
 		     */
 		    tokstr = NULL;
 		    return INPAR;
+		    
+		case CMD_OR_MATH_ERR:
+		    /*
+		     * LEXFLAGS_ACTIVE means we came from bufferwords(),
+		     * so we treat as an incomplete math expression
+		     */
+		    if (lexflags & LEXFLAGS_ACTIVE)
+			tokstr = dyncat("((", tokstr ? tokstr : "");
+		    /* fall through */
 
 		default:
 		    return LEXERR;