diff --git a/ChangeLog b/ChangeLog
index ee0b8bf328..72dc33f732 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Nov 13 10:36:39 2015  Victor Nawothnig  <Victor.Nawothnig@gmail.com>
+
+	* parse.y (new_unless): optimize constant condition for `unless`
+	  as well as `if`.  [Fix GH-1092]
+
 Fri Nov 13 10:08:41 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
 
 	* ext/psych/psych.gemspec: bump version to 2.0.15
diff --git a/parse.y b/parse.y
index 8b26b83da1..e6d2f37704 100644
--- a/parse.y
+++ b/parse.y
@@ -387,6 +387,7 @@ static NODE *cond_gen(struct parser_params*,NODE*);
 #define cond(node) cond_gen(parser, (node))
 static NODE *new_if_gen(struct parser_params*,NODE*,NODE*,NODE*);
 #define new_if(cc,left,right) new_if_gen(parser, (cc), (left), (right))
+#define new_unless(cc,left,right) new_if_gen(parser, (cc), (right), (left))
 static NODE *logop_gen(struct parser_params*,enum node_type,NODE*,NODE*);
 #define logop(type,node1,node2) logop_gen(parser, (type), (node1), (node2))
 
@@ -1177,7 +1178,7 @@ stmt		: keyword_alias fitem {lex_state = EXPR_FNAME;} fitem
 		| stmt modifier_unless expr_value
 		    {
 		    /*%%%*/
-			$$ = NEW_UNLESS(cond($3), remove_begin($1), 0);
+			$$ = new_unless($3, remove_begin($1), 0);
 			fixpos($$, $3);
 		    /*%
 			$$ = dispatch2(unless_mod, $3, $1);
@@ -2851,7 +2852,7 @@ primary		: literal
 		  k_end
 		    {
 		    /*%%%*/
-			$$ = NEW_UNLESS(cond($2), $4, $5);
+			$$ = new_unless($2, $4, $5);
 			fixpos($$, $2);
 		    /*%
 			$$ = dispatch3(unless, $2, $4, escape_Qundef($5));