From: Eric Ludlam <eric@siege-engine.com>
Date: Fri, 16 Oct 2015 20:37:48 +0000 (-0400)
Subject: semantic: C grammar optimizations
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=8daca76a3292e7f5faca95628144d2f06972fa93;p=emacs.git

semantic: C grammar optimizations

* admin/grammars/c.by (extern-c, c-or-cpp, opt-extern-c-contents):
 Optimize out all the extra EXTERN matches.
---

diff --git a/admin/grammars/c.by b/admin/grammars/c.by
index 06d58bdfe7e..ccdf8087804 100644
--- a/admin/grammars/c.by
+++ b/admin/grammars/c.by
@@ -240,20 +240,24 @@ extern-c-contents
   ;
 
 extern-c
-  : EXTERN C semantic-list
+  : EXTERN c-or-cpp opt-extern-c-contents
  ;; Extern C commands which contain a list need to have the
  ;; entries of the list extracted, and spliced into the main
  ;; list of entries.  This must be done via the function
  ;; that expands singular nonterminals, such as int x,y;
-    (TAG "C" 'extern :members (EXPANDFULL $3 extern-c-contents) )
-  | EXTERN CPP semantic-list
-    (TAG "C" 'extern :members (EXPANDFULL $3 extern-c-contents) )
-  | EXTERN C
- ;; A plain extern "C" call should add something to the token,
- ;; but just strip it from the buffer here for now.
-    ( nil )
-  | EXTERN CPP
-    ( nil )
+    (TAG (car $2) 'extern :members $3)
+  ;
+
+c-or-cpp
+  : C
+  | CPP
+  ;
+
+opt-extern-c-contents
+  : semantic-list
+    (EXPANDFULL $1 extern-c-contents)
+  | ;; EMPTY
+    ()
   ;
 
 macro