From bb8f7e7a4e6e45962dfadc3c7e840d25210dbe0f Mon Sep 17 00:00:00 2001
From: akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Fri, 4 Jan 2008 17:21:53 +0000
Subject: * include/ruby/ruby.h (rb_intern): memorize interned ID for constant 
  string, using gcc's __builtin_constant_p and statement expression.

git-svn-id: http://svn.ruby-lang.org/repos/ruby/trunk@14888 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 include/ruby/ruby.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

(limited to 'include/ruby')

diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 3f2883728..ecc9bfd92 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -719,6 +719,20 @@ const char *rb_id2name(ID);
 ID rb_to_id(VALUE);
 VALUE rb_id2str(ID);
 
+#ifdef __GNUC__
+/* __builtin_constant_p and statement expression is available
+ * since gcc-2.7.2.3 at least. */
+#define rb_intern(str) \
+    (__builtin_constant_p(str) ? \
+        ({ \
+            static ID rb_intern_id_cache; \
+            if (!rb_intern_id_cache) \
+                rb_intern_id_cache = rb_intern(str); \
+            rb_intern_id_cache; \
+        }) : \
+        rb_intern(str))
+#endif
+
 char *rb_class2name(VALUE);
 char *rb_obj_classname(VALUE);
 
-- 
cgit