* include/ruby/ruby.h (CONST_ID): constant ID cache for non-gcc.

* *.c: no cache in init functions.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@17053 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

32 files changed, 141 insertions, 85 deletions

diff --git a/ChangeLog b/ChangeLog
index 6a7f6145f2..3727381668 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Mon Jun  9 18:25:30 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* include/ruby/ruby.h (CONST_ID): constant ID cache for non-gcc.
+
+	* *.c: no cache in init functions.
+
 Mon Jun  9 17:56:30 2008  Akinori MUSHA  <knu@iDaemons.org>
 
 	* lib/set.rb (Set#delete_if): Call to_a.
diff --git a/array.c b/array.c
index fdf1808753..fef44e462b 100644
--- a/array.c
+++ b/array.c
@@ -3400,6 +3400,8 @@ rb_ary_drop_while(VALUE ary)
 void
 Init_Array(void)
 {
+#undef rb_intern
+
     rb_cArray  = rb_define_class("Array", rb_cObject);
     rb_include_module(rb_cArray, rb_mEnumerable);
 
diff --git a/blockinlining.c b/blockinlining.c
index c2878d933c..3f4aa86fe5 100644
--- a/blockinlining.c
+++ b/blockinlining.c
@@ -129,9 +129,11 @@ build_Integer_times_node(rb_iseq_t *iseq, NODE * node, NODE * lnode,
        end
        }
      */
-    ID _self = rb_intern("#_self");
+    ID _self;
+    CONST_ID(_self, "#_self");
     if (iseq->argc == 0) {
-	ID e = rb_intern("#e");
+	ID e;
+	CONST_ID(e, "#e");
 	rb_ary_push(param_vars, ID2SYM(e));
 	rb_ary_push(param_vars, ID2SYM(_self));
 	iseq->argc += 2;
@@ -145,10 +147,11 @@ build_Integer_times_node(rb_iseq_t *iseq, NODE * node, NODE * lnode,
 		      Qundef);
     }
     else {
-	ID _e = rb_intern("#_e");
+	ID _e;
 	ID e = SYM2ID(rb_ary_entry(param_vars, 0));
 	NODE *assign;
 
+	CONST_ID(_e, "#_e");
 	rb_ary_push(param_vars, ID2SYM(_self));
 	rb_ary_push(local_vars, ID2SYM(_e));
 	iseq->argc++;
@@ -230,9 +233,11 @@ build_Range_each_node(rb_iseq_t *iseq, NODE * node, NODE * lnode,
        end
        }
      */
-    ID _last = rb_intern("#_last");
+    ID _last;
+    CONST_ID(_last, "#_last");
     if (iseq->argc == 0) {
-	ID e = rb_intern("#e");
+	ID e;
+	CONST_ID(e, "#e");
 	rb_ary_push(param_vars, ID2SYM(e));
 	rb_ary_push(param_vars, ID2SYM(_last));
 	iseq->argc += 2;
@@ -245,10 +250,11 @@ build_Range_each_node(rb_iseq_t *iseq, NODE * node, NODE * lnode,
 		      Qundef);
     }
     else {
-	ID _e = rb_intern("#_e");
+	ID _e;
 	ID e = SYM2ID(rb_ary_entry(param_vars, 0));
 	NODE *assign;
 
+	CONST_ID(_e, "#_e");
 	rb_ary_push(param_vars, ID2SYM(_last));
 	rb_ary_push(local_vars, ID2SYM(_e));
 	iseq->argc++;
@@ -362,11 +368,13 @@ build_Array_each_node(rb_iseq_t *iseq, NODE * node, NODE * lnode,
        }
      */
 
-    ID _self = rb_intern("#_self");
-    ID _i = rb_intern("#_i");
+    ID _self, _i;
 
+    CONST_ID(_self, "#_self");
+    CONST_ID(_i, "#_i");
     if (iseq->argc == 0) {
-	ID _e = rb_intern("#_e");
+	ID _e;
+	CONST_ID(_e, "#_e");
 	rb_ary_push(param_vars, ID2SYM(_e));
 	rb_ary_push(param_vars, ID2SYM(_self));
 	iseq->argc += 2;
diff --git a/class.c b/class.c
index 60bd2e30be..0d612a5e87 100644
--- a/class.c
+++ b/class.c
@@ -102,9 +102,9 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
 	ID id;
 
 	RCLASS_IV_TBL(clone) = st_copy(RCLASS_IV_TBL(orig));
-	id = rb_intern("__classpath__");
+	CONST_ID(id, "__classpath__");
 	st_delete(RCLASS_IV_TBL(clone), (st_data_t*)&id, 0);
-	id = rb_intern("__classid__");
+	CONST_ID(id, "__classid__");
 	st_delete(RCLASS_IV_TBL(clone), (st_data_t*)&id, 0);
     }
     if (RCLASS_M_TBL(orig)) {
@@ -169,10 +169,12 @@ void
 rb_singleton_class_attached(VALUE klass, VALUE obj)
 {
     if (FL_TEST(klass, FL_SINGLETON)) {
+	ID attached;
 	if (!RCLASS_IV_TBL(klass)) {
 	    RCLASS_IV_TBL(klass) = st_init_numtable();
 	}
-	st_insert(RCLASS_IV_TBL(klass), rb_intern("__attached__"), obj);
+	CONST_ID(attached, "__attached__");
+	st_insert(RCLASS_IV_TBL(klass), attached, obj);
     }
 }
 
@@ -214,8 +216,10 @@ rb_define_class_id(ID id, VALUE super)
 VALUE
 rb_class_inherited(VALUE super, VALUE klass)
 {
+    ID inherited;
     if (!super) super = rb_cObject;
-    return rb_funcall(super, rb_intern("inherited"), 1, klass);
+    CONST_ID(inherited, "inherited");
+    return rb_funcall(super, inherited, 1, klass);
 }
 
 VALUE
diff --git a/compar.c b/compar.c
index 55b217a60a..b028a256ec 100644
--- a/compar.c
+++ b/compar.c
@@ -198,6 +198,8 @@ cmp_between(VALUE x, VALUE min, VALUE max)
 void
 Init_Comparable(void)
 {
+#undef rb_intern
+
     rb_mComparable = rb_define_module("Comparable");
     rb_define_method(rb_mComparable, "==", cmp_equal, 1);
     rb_define_method(rb_mComparable, ">", cmp_gt, 1);
diff --git a/compile.c b/compile.c
index 7362a0e6a5..0424a83884 100644
--- a/compile.c
+++ b/compile.c
@@ -761,11 +761,9 @@ iseq_setup(rb_iseq_t *iseq, LINK_ANCHOR *anchor)
 static int
 iseq_set_exception_local_table(rb_iseq_t *iseq)
 {
-    static ID id_dollar_bang;
+    ID id_dollar_bang;
 
-    if (!id_dollar_bang) {
-	id_dollar_bang = rb_intern("#$!");
-    }
+    CONST_ID(id_dollar_bang, "#$!");
     iseq->local_table = (ID *)ALLOC_N(ID *, 1);
     iseq->local_table_size = 1;
     iseq->local_size = iseq->local_table_size + 1;
@@ -3718,15 +3716,14 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 	}
 	/* only joke */
 	{
-	    static ID goto_id;
-	    static ID label_id;
+	    ID goto_id;
+	    ID label_id;
 	    VALUE label;
 	    VALUE label_sym;
 
-	    if (goto_id == 0) {
-		goto_id = rb_intern("__goto__");
-		label_id = rb_intern("__label__");
-	    }
+	    
+	    CONST_ID(goto_id, "__goto__");
+	    CONST_ID(label_id, "__label__");
 
 	    if (nd_type(node) == NODE_FCALL &&
 		(mid == goto_id || mid == label_id)) {
@@ -4319,14 +4316,16 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 	break;
       }
       case NODE_SCLASS:{
+	ID singletonclass;
 	VALUE iseqval =
 	    NEW_ISEQVAL(node->nd_body, rb_str_new2("singletonclass"),
 			ISEQ_TYPE_CLASS);
 
 	COMPILE(ret, "sclass#recv", node->nd_recv);
 	ADD_INSN (ret, nd_line(node), putnil);
+	CONST_ID(singletonclass, "singletonclass");
 	ADD_INSN3(ret, nd_line(node), defineclass,
-		  ID2SYM(rb_intern("singletonclass")), iseqval, INT2FIX(1));
+		  ID2SYM(singletonclass), iseqval, INT2FIX(1));
 
 	if (poped) {
 	    ADD_INSN(ret, nd_line(node), pop);
@@ -4787,6 +4786,7 @@ register_label(rb_iseq_t *iseq, struct st_table *labels_table, VALUE obj)
 static VALUE
 get_exception_sym2type(VALUE sym)
 {
+#undef rb_intern
     static VALUE symRescue, symEnsure, symRetry;
     static VALUE symBreak, symRedo, symNext;
 
diff --git a/complex.c b/complex.c
index 16bf8f05b4..6bc004a5d0 100644
--- a/complex.c
+++ b/complex.c
@@ -1387,6 +1387,8 @@ numeric_conjugate(VALUE self)
 void
 Init_Complex(void)
 {
+#undef rb_intern
+
     assert(fprintf(stderr, "assert() is now active\n"));
 
     id_Unify = rb_intern("Unify");
diff --git a/encoding.c b/encoding.c
index b1fc140ad9..0928b4b2b0 100644
--- a/encoding.c
+++ b/encoding.c
@@ -533,9 +533,7 @@ enc_check_capable(VALUE x)
 ID
 rb_id_encoding(void)
 {
-    if (!id_encoding) {
-	id_encoding = rb_intern("encoding");
-    }
+    CONST_ID(id_encoding, "encoding");
     return id_encoding;
 }
 
@@ -1162,6 +1160,8 @@ rb_enc_aliases(VALUE klass)
 void
 Init_Encoding(void)
 {
+#undef rb_intern
+
     id_base_encoding = rb_intern("#base_encoding");
 
     rb_cEncoding = rb_define_class("Encoding", rb_cObject);
diff --git a/enum.c b/enum.c
index 7a7f180161..e4d4ee5969 100644
--- a/enum.c
+++ b/enum.c
@@ -1566,7 +1566,7 @@ enum_zip(int argc, VALUE *argv, VALUE obj)
 	}
     }
     if (!allary) {
-	conv = rb_intern("to_enum");
+	CONST_ID(conv, "to_enum");
 	for (i=0; i<argc; i++) {
 	    argv[i] = rb_funcall(argv[i], conv, 1, ID2SYM(id_each));
 	}
@@ -1800,6 +1800,8 @@ enum_cycle(int argc, VALUE *argv, VALUE obj)
 void
 Init_Enumerable(void)
 {
+#undef rb_intern
+
     rb_mEnumerable = rb_define_module("Enumerable");
 
     rb_define_method(rb_mEnumerable, "to_a", enum_to_a, -1);
diff --git a/error.c b/error.c
index f339fb3858..2210a705af 100644
--- a/error.c
+++ b/error.c
@@ -496,9 +496,9 @@ exc_inspect(VALUE exc)
 static VALUE
 exc_backtrace(VALUE exc)
 {
-    static ID bt;
+    ID bt;
 
-    if (!bt) bt = rb_intern("bt");
+    CONST_ID(bt, "bt");
     return rb_attr_get(exc, bt);
 }
 
@@ -506,7 +506,7 @@ VALUE
 rb_check_backtrace(VALUE bt)
 {
     long i;
-    static const char *err = "backtrace must be Array of String";
+    static const char err[] = "backtrace must be Array of String";
 
     if (!NIL_P(bt)) {
 	int t = TYPE(bt);
@@ -552,11 +552,12 @@ exc_set_backtrace(VALUE exc, VALUE bt)
 static VALUE
 exc_equal(VALUE exc, VALUE obj)
 {
-    ID id_mesg = rb_intern("mesg");
+    ID id_mesg;
 
     if (exc == obj) return Qtrue;
     if (rb_obj_class(exc) != rb_obj_class(obj))
 	return rb_equal(obj, exc);
+    CONST_ID(id_mesg, "mesg");
     if (!rb_equal(rb_attr_get(exc, id_mesg), rb_attr_get(obj, id_mesg)))
 	return Qfalse;
     if (!rb_equal(exc_backtrace(exc), exc_backtrace(obj)))
@@ -963,7 +964,9 @@ static VALUE
 syserr_eqq(VALUE self, VALUE exc)
 {
     VALUE num, e;
-    ID en = rb_intern("errno");
+    ID en;
+
+    CONST_ID(en, "errno");
 
     if (!rb_obj_is_kind_of(exc, rb_eSystemCallError)) {
 	if (!rb_respond_to(exc, en)) return Qfalse;
diff --git a/eval.c b/eval.c
index 7cd2a22404..167dea77ff 100644
--- a/eval.c
+++ b/eval.c
@@ -507,7 +507,7 @@ rb_make_exception(int argc, VALUE *argv)
       case 3:
 	n = 1;
       exception_call:
-	exception = rb_intern("exception");
+	CONST_ID(exception, "exception");
 	if (!rb_respond_to(argv[0], exception)) {
 	    rb_raise(rb_eTypeError, "exception class/object expected");
 	}
diff --git a/file.c b/file.c
index 1d1fab254d..5b99cf05b7 100644
--- a/file.c
+++ b/file.c
@@ -102,15 +102,14 @@ static VALUE
 rb_get_path_check(VALUE obj, int check)
 {
     VALUE tmp;
-    static ID to_path;
+    ID to_path;
 
     if (check) rb_check_safe_obj(obj);
     tmp = rb_check_string_type(obj);
     if (!NIL_P(tmp)) goto exit;
 
-    if (!to_path) {
-	to_path = rb_intern("to_path");
-    }
+
+    CONST_ID(to_path, "to_path");
     if (rb_respond_to(obj, to_path)) {
 	tmp = rb_funcall(obj, to_path, 0, 0);
     }
diff --git a/hash.c b/hash.c
index b5a0c685b5..89139e852f 100644
--- a/hash.c
+++ b/hash.c
@@ -2564,6 +2564,8 @@ env_update(VALUE env, VALUE hash)
 void
 Init_Hash(void)
 {
+#undef rb_intern
+
     id_hash = rb_intern("hash");
     id_yield = rb_intern("yield");
     id_default = rb_intern("default");
diff --git a/id.c b/id.c
index c5d7e3642b..0226a9f5aa 100644
--- a/id.c
+++ b/id.c
@@ -18,6 +18,8 @@
 void
 Init_id(void)
 {
+#undef rb_intern
+
     /* Symbols */
     symIFUNC = ID2SYM(rb_intern("<IFUNC>"));
     symCFUNC = ID2SYM(rb_intern("<CFUNC>"));
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 614a6145b3..99321f1933 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -764,17 +764,21 @@ const char *rb_id2name(ID);
 ID rb_to_id(VALUE);
 VALUE rb_id2str(ID);
 
+#define CONST_ID_CACHE(result, str)			\
+    ({							\
+	static ID rb_intern_id_cache;			\
+	if (!rb_intern_id_cache)			\
+	    rb_intern_id_cache = (rb_intern)(str);	\
+	result rb_intern_id_cache;			\
+    })
+#define CONST_ID(var, str) \
+    do {CONST_ID_CACHE(var =, str);} while (0)
 #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; \
-        }) : \
+        CONST_ID_CACHE(/**/, str) : \
         rb_intern(str))
 #endif
 
diff --git a/io.c b/io.c
index 2cad50cc05..d5ffa0cf6c 100644
--- a/io.c
+++ b/io.c
@@ -4231,7 +4231,7 @@ rb_f_open(int argc, VALUE *argv)
     int redirect = Qfalse;
 
     if (argc >= 1) {
-	to_open = rb_intern("to_open");
+	CONST_ID(to_open, "to_open");
 	if (rb_respond_to(argv[0], to_open)) {
 	    redirect = Qtrue;
 	}
@@ -6178,11 +6178,11 @@ open_key_args(int argc, VALUE *argv, struct foreach_arg *arg)
     if (!encoding) {
 	ID id;
 
-	id = rb_intern("encoding");
+	CONST_ID(id, "encoding");
 	encoding = ID2SYM(id);
-	id = rb_intern("mode");
+	CONST_ID(id, "mode");
 	mode = ID2SYM(id);
-	id = rb_intern("open_args");
+	CONST_ID(id, "open_args");
 	open_args = ID2SYM(id);
     }
     v = rb_hash_aref(opt, open_args);
@@ -7484,6 +7484,8 @@ rb_get_argv(void)
 void
 Init_IO(void)
 {
+#undef rb_intern
+
     VALUE rb_cARGF;
 #ifdef __CYGWIN__
 #include <sys/cygwin.h>
diff --git a/iseq.c b/iseq.c
index b8a84ed402..e09c9c4ae6 100644
--- a/iseq.c
+++ b/iseq.c
@@ -956,12 +956,12 @@ exception_type2symbol(VALUE type)
 {
     ID id;
     switch(type) {
-      case CATCH_TYPE_RESCUE: id = rb_intern("rescue"); break;
-      case CATCH_TYPE_ENSURE: id = rb_intern("ensure"); break;
-      case CATCH_TYPE_RETRY:  id = rb_intern("retry");  break;
-      case CATCH_TYPE_BREAK:  id = rb_intern("break");  break;
-      case CATCH_TYPE_REDO:   id = rb_intern("redo");   break;
-      case CATCH_TYPE_NEXT:   id = rb_intern("next");   break;
+      case CATCH_TYPE_RESCUE: CONST_ID(id, "rescue"); break;
+      case CATCH_TYPE_ENSURE: CONST_ID(id, "ensure"); break;
+      case CATCH_TYPE_RETRY:  CONST_ID(id, "retry");  break;
+      case CATCH_TYPE_BREAK:  CONST_ID(id, "break");  break;
+      case CATCH_TYPE_REDO:   CONST_ID(id, "redo");   break;
+      case CATCH_TYPE_NEXT:   CONST_ID(id, "next");   break;
       default:
 	rb_bug("...");
     }
diff --git a/marshal.c b/marshal.c
index 9f22cdcc88..692b37de93 100644
--- a/marshal.c
+++ b/marshal.c
@@ -1669,6 +1669,8 @@ marshal_load(int argc, VALUE *argv)
 void
 Init_marshal(void)
 {
+#undef rb_intern
+
     VALUE rb_mMarshal = rb_define_module("Marshal");
 
     s_dump = rb_intern("_dump");
diff --git a/numeric.c b/numeric.c
index 6374982c3f..318d6046f3 100644
--- a/numeric.c
+++ b/numeric.c
@@ -3092,6 +3092,8 @@ fix_even_p(VALUE num)
 void
 Init_Numeric(void)
 {
+#undef rb_intern
+
 #if defined(__FreeBSD__) && __FreeBSD__ < 4
     /* allow divide by zero -- Inf */
     fpsetmask(fpgetmask() & ~(FP_X_DZ|FP_X_INV|FP_X_OFL));
diff --git a/object.c b/object.c
index 70e7f19833..0d18ea5b29 100644
--- a/object.c
+++ b/object.c
@@ -2365,6 +2365,8 @@ boot_defclass(const char *name, VALUE super)
 void
 Init_Object(void)
 {
+#undef rb_intern
+
     VALUE metaclass;
 
     rb_cBasicObject = boot_defclass("BasicObject", 0);
diff --git a/parse.y b/parse.y
index 31694a3717..48a777eb72 100644
--- a/parse.y
+++ b/parse.y
@@ -7761,9 +7761,9 @@ assignable_gen(struct parser_params *parser, ID id, NODE *val)
 static void
 shadowing_lvar_gen(struct parser_params *parser, ID name)
 {
-    static ID uscore;
+    ID uscore;
 
-    if (!uscore) uscore = rb_intern("_");
+    CONST_ID(uscore, "_");
     if (uscore == name) return;
     if (dyna_in_block()) {
 	if (dvar_curr(name)) {
diff --git a/prec.c b/prec.c
index c2e3032b7c..3b245248c5 100644
--- a/prec.c
+++ b/prec.c
@@ -124,6 +124,8 @@ prec_included(VALUE module, VALUE include)
 void
 Init_Precision(void)
 {
+#undef rb_intern
+
     rb_mPrecision = rb_define_module("Precision");
     rb_define_singleton_method(rb_mPrecision, "included", prec_included, 1);
     rb_define_method(rb_mPrecision, "prec", prec_prec, 1);
diff --git a/range.c b/range.c
index 45ba78dcf7..3b19a2b33e 100644
--- a/range.c
+++ b/range.c
@@ -896,6 +896,8 @@ range_alloc(VALUE klass)
 void
 Init_Range(void)
 {
+#undef rb_intern
+
     id_cmp = rb_intern("<=>");
     id_succ = rb_intern("succ");
     id_beg = rb_intern("begin");
diff --git a/rational.c b/rational.c
index aaf1d3a8cc..8bf786a166 100644
--- a/rational.c
+++ b/rational.c
@@ -1501,6 +1501,8 @@ nurat_s_induced_from(VALUE klass, VALUE n)
 void
 Init_Rational(void)
 {
+#undef rb_intern
+
     assert(fprintf(stderr, "assert() is now active\n"));
 
     id_Unify = rb_intern("Unify");
diff --git a/ruby.c b/ruby.c
index f6c3a43f80..a8945ea0d7 100644
--- a/ruby.c
+++ b/ruby.c
@@ -452,9 +452,10 @@ static void
 require_libraries(struct cmdline_options *opt)
 {
     VALUE list = opt->req_list;
-    ID require = rb_intern("require");
+    ID require;
 
     Init_ext();		/* should be called here for some reason :-( */
+    CONST_ID(require, "require");
     while (list && RARRAY_LEN(list) > 0) {
 	VALUE feature = rb_ary_shift(list);
 	rb_funcall2(rb_vm_top_self(), require, 1, &feature);
diff --git a/string.c b/string.c
index 68a4c55990..ef54b7e459 100644
--- a/string.c
+++ b/string.c
@@ -2632,7 +2632,7 @@ rb_str_upto(int argc, VALUE *argv, VALUE beg)
 
     rb_scan_args(argc, argv, "11", &end, &exclusive);
     excl = RTEST(exclusive);
-    succ = rb_intern("succ");
+    CONST_ID(succ, "succ");
     StringValue(end);
     enc = rb_enc_check(beg, end);
     if (RSTRING_LEN(beg) == 1 && RSTRING_LEN(end) == 1 &&
@@ -6526,6 +6526,8 @@ rb_to_id(VALUE name)
 void
 Init_String(void)
 {
+#undef rb_intern
+
     rb_cString  = rb_define_class("String", rb_cObject);
     rb_include_module(rb_cString, rb_mComparable);
     rb_define_alloc_func(rb_cString, str_alloc);
diff --git a/thread.c b/thread.c
index 298d1c1ddb..522c786c45 100644
--- a/thread.c
+++ b/thread.c
@@ -3167,6 +3167,8 @@ ruby_suppress_tracing(VALUE (*func)(VALUE, int), VALUE arg, int always)
 void
 Init_Thread(void)
 {
+#undef rb_intern
+
     VALUE cThGroup;
 
     rb_define_singleton_method(rb_cThread, "new", thread_s_new, -1);
diff --git a/time.c b/time.c
index f6e97244a4..c35c9a15f4 100644
--- a/time.c
+++ b/time.c
@@ -2338,6 +2338,8 @@ time_load(VALUE klass, VALUE str)
 void
 Init_Time(void)
 {
+#undef rb_intern
+
     id_divmod = rb_intern("divmod");
     id_mul = rb_intern("*");
     id_submicro = rb_intern("submicro");
diff --git a/variable.c b/variable.c
index 14cac18149..3185d8a3c6 100644
--- a/variable.c
+++ b/variable.c
@@ -26,9 +26,9 @@ Init_var_tables(void)
 {
     rb_global_tbl = st_init_numtable();
     rb_class_tbl = st_init_numtable();
-    autoload = rb_intern("__autoload__");
-    classpath = rb_intern("__classpath__");
-    tmp_classpath = rb_intern("__tmp_classpath__");
+    CONST_ID(autoload, "__autoload__");
+    CONST_ID(classpath, "__classpath__");
+    CONST_ID(tmp_classpath, "__tmp_classpath__");
 }
 
 struct fc_result {
@@ -142,7 +142,9 @@ classname(VALUE klass)
     if (!klass) klass = rb_cObject;
     if (RCLASS_IV_TBL(klass)) {
 	if (!st_lookup(RCLASS_IV_TBL(klass), classpath, &path)) {
-	    ID classid = rb_intern("__classid__");
+	    ID classid;
+
+	    CONST_ID(classid, "__classid__");
 
 	    if (!st_lookup(RCLASS_IV_TBL(klass), classid, &path)) {
 		return find_class_path(klass);
diff --git a/vm.c b/vm.c
index a62392c3c0..5ac1e6771b 100644
--- a/vm.c
+++ b/vm.c
@@ -754,22 +754,22 @@ make_localjump_error(const char *mesg, VALUE value, int reason)
 
     switch (reason) {
       case TAG_BREAK:
-	id = rb_intern("break");
+	CONST_ID(id, "break");
 	break;
       case TAG_REDO:
-	id = rb_intern("redo");
+	CONST_ID(id, "redo");
 	break;
       case TAG_RETRY:
-	id = rb_intern("retry");
+	CONST_ID(id, "retry");
 	break;
       case TAG_NEXT:
-	id = rb_intern("next");
+	CONST_ID(id, "next");
 	break;
       case TAG_RETURN:
-	id = rb_intern("return");
+	CONST_ID(id, "return");
 	break;
       default:
-	id = rb_intern("noreason");
+	CONST_ID(id, "noreason");
 	break;
     }
     rb_iv_set(exc, "@exit_value", value);
@@ -1241,7 +1241,7 @@ rb_thread_method_id_and_class(rb_thread_t *th,
     }
     while (iseq) {
 	if (RUBY_VM_IFUNC_P(iseq)) {
-	    if (idp) *idp = rb_intern("<ifunc>");
+	    if (idp) CONST_ID(*idp, "<ifunc>");
 	    if (klassp) *klassp = 0;
 	    return 1;
 	}
diff --git a/vm_dump.c b/vm_dump.c
index c9e0657755..80bb13eb77 100644
--- a/vm_dump.c
+++ b/vm_dump.c
@@ -425,18 +425,16 @@ debug_print_post(rb_thread_t *th, rb_control_frame_t *cfp
 void
 vm_analysis_insn(int insn)
 {
-    static ID usage_hash;
-    static ID bigram_hash;
+    ID usage_hash;
+    ID bigram_hash;
     static int prev_insn = -1;
 
     VALUE uh;
     VALUE ihash;
     VALUE cv;
 
-    if (usage_hash == 0) {
-	usage_hash = rb_intern("USAGE_ANALYSIS_INSN");
-	bigram_hash = rb_intern("USAGE_ANALYSIS_INSN_BIGRAM");
-    }
+    CONST_ID(usage_hash, "USAGE_ANALYSIS_INSN");
+    CONST_ID(bigram_hash, "USAGE_ANALYSIS_INSN_BIGRAM");
     uh = rb_const_get(rb_cVM, usage_hash);
     if ((ihash = rb_hash_aref(uh, INT2FIX(insn))) == Qnil) {
 	ihash = rb_hash_new();
@@ -473,7 +471,7 @@ extern VALUE insn_operand_intern(int insn, int op_no, VALUE op,
 void
 vm_analysis_operand(int insn, int n, VALUE op)
 {
-    static ID usage_hash;
+    ID usage_hash;
 
     VALUE uh;
     VALUE ihash;
@@ -481,9 +479,7 @@ vm_analysis_operand(int insn, int n, VALUE op)
     VALUE valstr;
     VALUE cv;
 
-    if (usage_hash == 0) {
-	usage_hash = rb_intern("USAGE_ANALYSIS_INSN");
-    }
+    CONST_ID(usage_hash, "USAGE_ANALYSIS_INSN");
 
     uh = rb_const_get(rb_cVM, usage_hash);
     if ((ihash = rb_hash_aref(uh, INT2FIX(insn))) == Qnil) {
@@ -507,11 +503,11 @@ vm_analysis_operand(int insn, int n, VALUE op)
 void
 vm_analysis_register(int reg, int isset)
 {
-    static ID usage_hash;
+    ID usage_hash;
     VALUE uh;
     VALUE rhash;
     VALUE valstr;
-    char *regstrs[] = {
+    static const char regstrs[][5] = {
 	"pc",			/* 0 */
 	"sp",			/* 1 */
 	"cfp",			/* 2 */
@@ -520,7 +516,7 @@ vm_analysis_register(int reg, int isset)
 	"self",			/* 5 */
 	"iseq",			/* 6 */
     };
-    char *getsetstr[] = {
+    static const char getsetstr[][4] = {
 	"get",
 	"set",
     };
@@ -528,12 +524,11 @@ vm_analysis_register(int reg, int isset)
 
     VALUE cv;
 
-    if (usage_hash == 0) {
+    CONST_ID(usage_hash, "USAGE_ANALYSIS_REGS");
+    if (syms[0] == 0) {
 	char buff[0x10];
 	int i;
 
-	usage_hash = rb_intern("USAGE_ANALYSIS_REGS");
-
 	for (i = 0; i < sizeof(regstrs) / sizeof(regstrs[0]); i++) {
 	    int j;
 	    for (j = 0; j < 2; j++) {
diff --git a/vm_method.c b/vm_method.c
index d7160fcd9d..ec9634fcda 100644
--- a/vm_method.c
+++ b/vm_method.c
@@ -1105,6 +1105,8 @@ obj_respond_to(int argc, VALUE *argv, VALUE obj)
 void
 Init_eval_method(void)
 {
+#undef rb_intern
+
     rb_define_method(rb_mKernel, "respond_to?", obj_respond_to, -1);
     basic_respond_to = rb_method_node(rb_cObject, idRespond_to);
     rb_register_mark_object((VALUE)basic_respond_to);