* parse.y (str_extend): shuould allow interpolation of $-x.

* variable.c (rb_cvar_set): empty iv_tbl may cause infinite loop.

* variable.c (rb_cvar_get): ditto.

* variable.c (cvar_override_check): ditto.

* bignum.c (rb_big_eq): convert Bignum to Float, instead of
  reverse.

* time.c (time_localtime): getting tm should not be prohibited for
  frozen time objects.

* time.c (time_gmtime): ditto.

* version.c (Init_version): freeze RUBY_VERSION,
  RUBY_RELEASE_DATE, and RUBY_PLATFORM.

* file.c (Init_File): freeze File::SEPARATOR, ALT_SEPARATOR and
  PATH_SEPARATOR.

* file.c (rb_stat_cmp): should check operand type before calling
  get_stat().

* eval.c (rb_eval_cmd): should not invoke "call" with a block on
  any occasion.

* numeric.c (fix_aref): idx may be a Bignum.

* numeric.c (num_remainder): a bug in Numeric#remainder.

* eval.c (rb_exec_end_proc): END might be called within END
  block.

* class.c (rb_mod_clone): should not copy class name, since clone
  should remain anonymous.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@1800 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

20 files changed, 174 insertions, 77 deletions

diff --git a/ChangeLog b/ChangeLog
index f54218b017..99dc250977 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,43 @@
+Mon Oct 29 07:57:31 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* parse.y (str_extend): shuould allow interpolation of $-x.
+
+	* variable.c (rb_cvar_set): empty iv_tbl may cause infinite loop.
+
+	* variable.c (rb_cvar_get): ditto.
+
+	* variable.c (cvar_override_check): ditto.
+
+Sat Oct 27 23:01:19 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* bignum.c (rb_big_eq): convert Bignum to Float, instead of
+	  reverse.
+
+Fri Oct 26 06:19:29 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* time.c (time_localtime): getting tm should not be prohibited for
+	  frozen time objects.
+
+	* time.c (time_gmtime): ditto.
+
+	* version.c (Init_version): freeze RUBY_VERSION,
+	  RUBY_RELEASE_DATE, and RUBY_PLATFORM.
+
+	* file.c (Init_File): freeze File::SEPARATOR, ALT_SEPARATOR and
+	  PATH_SEPARATOR.
+
+	* file.c (rb_stat_cmp): should check operand type before calling
+	  get_stat().
+
+Thu Oct 25 10:28:15 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* eval.c (rb_eval_cmd): should not invoke "call" with a block on
+	  any occasion.
+
+Wed Oct 24 03:25:31 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* numeric.c (fix_aref): idx may be a Bignum.
+
 Tue Oct 23 01:21:19 2001  Nobuyoshi Nakada  <nobu.nakada@nifty.ne.jp>
 
 	* eval.c (proc_invoke): fix self switching in Proc#call
@@ -43,8 +83,15 @@ Tue Oct 23 01:15:43 2001  K.Kosako  <kosako@sofnec.co.jp>
 
 	* variable.c (rb_alias_variable): ditto.
 
+Mon Oct 22 18:53:55 2001  Masahiro Tanaka  <masa@stars.gsfc.nasa.gov>
+
+	* numeric.c (num_remainder): a bug in Numeric#remainder.
+
 Mon Oct 22 15:21:55 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
+	* eval.c (rb_exec_end_proc): END might be called within END
+	  block.
+
 	* class.c (rb_mod_clone): should not copy class name, since clone
 	  should remain anonymous.
 
diff --git a/array.c b/array.c
index 747d33152c..79131901e3 100644
--- a/array.c
+++ b/array.c
@@ -890,7 +890,7 @@ inspect_ensure(obj)
 
 VALUE
 rb_protect_inspect(func, obj, arg)
-    VALUE (*func)();
+    VALUE (*func)(ANYARGS);
     VALUE obj, arg;
 {
     struct inspect_arg iarg;
diff --git a/bignum.c b/bignum.c
index 57a6958047..2a1601bf5b 100644
--- a/bignum.c
+++ b/bignum.c
@@ -593,8 +593,7 @@ rb_big_eq(x, y)
       case T_BIGNUM:
 	break;
       case T_FLOAT:
-	y = dbl2big(RFLOAT(y)->value);
-	break;
+	return (rb_big2dbl(x) == RFLOAT(y)->value)?Qtrue:Qfalse;
       default:
 	return Qfalse;
     }
diff --git a/error.c b/error.c
index 608708f787..06efcb83a2 100644
--- a/error.c
+++ b/error.c
@@ -734,14 +734,14 @@ rb_sys_fail(mesg)
 #ifdef __BEOS__
     ee = get_syserr(n);
     if (!ee) {
-	char name[6];
+	char name[12];
       
 	sprintf(name, "E%03d", n);
 	ee = set_syserr(n, name);
    }
 #else
     if (n > sys_nerr || !syserr_list[n]) {
-	char name[6];
+	char name[12];
 
 	sprintf(name, "E%03d", n);
 	ee = set_syserr(n, name);
diff --git a/eval.c b/eval.c
index e31c5986c9..5fb2213c75 100644
--- a/eval.c
+++ b/eval.c
@@ -1349,8 +1349,10 @@ rb_eval_cmd(cmd, arg)
     volatile int safe = ruby_safe_level;
 
     if (TYPE(cmd) != T_STRING) {
-	return rb_funcall2(cmd, rb_intern("call"),
-			   RARRAY(arg)->len, RARRAY(arg)->ptr);
+	PUSH_ITER(ITER_NOT);
+	val = rb_funcall2(cmd, rb_intern("call"), RARRAY(arg)->len, RARRAY(arg)->ptr);
+	POP_ITER();
+	return val;
     }
 
     saved_scope = ruby_scope;
@@ -2736,7 +2738,7 @@ rb_eval(self, n)
 		val = rb_funcall(val, node->nd_mid, 1, rb_eval(self, rval));
 	    }
 	    argv[argc-1] = val;
-	    val = rb_funcall2(recv, aset, argc, argv);
+	    rb_funcall2(recv, aset, argc, argv);
 	    result = val;
 	}
 	break;
@@ -3921,7 +3923,7 @@ assign(self, lhs, val, pcall)
 
 VALUE
 rb_iterate(it_proc, data1, bl_proc, data2)
-    VALUE (*it_proc)(), (*bl_proc)();
+    VALUE (*it_proc) _((VALUE)), (*bl_proc)(ANYARGS);
     VALUE data1, data2;
 {
     int state;
@@ -3995,10 +3997,10 @@ handle_rescue(self, node)
 
 VALUE
 #ifdef HAVE_STDARG_PROTOTYPES
-rb_rescue2(VALUE (*b_proc)(), VALUE data1, VALUE (*r_proc)(), VALUE data2, ...)
+rb_rescue2(VALUE (*b_proc)(ANYARGS), VALUE data1, VALUE (*r_proc)(ANYARGS), VALUE data2, ...)
 #else
 rb_rescue2(b_proc, data1, r_proc, data2, va_alist)
-    VALUE (*b_proc)(), (*r_proc)();
+    VALUE (*b_proc)(ANYARGS), (*r_proc)(ANYARGS);
     VALUE data1, data2;
     va_dcl
 #endif
@@ -4089,8 +4091,9 @@ rb_protect(proc, data, state)
 VALUE
 rb_ensure(b_proc, data1, e_proc, data2)
     VALUE (*b_proc)();
+    VALUE data1;
     VALUE (*e_proc)();
-    VALUE data1, data2;
+    VALUE data2;
 {
     int state;
     volatile VALUE result = Qnil;
@@ -5959,12 +5962,20 @@ rb_f_at_exit()
 void
 rb_exec_end_proc()
 {
-    struct end_proc_data *link;
+    struct end_proc_data *link, *save;
     int status;
 
-    link = end_procs;
+    save = link = end_procs;
     while (link) {
-	rb_protect((VALUE(*)_((VALUE)))link->func, link->data, &status);
+	rb_protect((VALUE(*)())link->func, link->data, &status);
+	if (status) {
+	    error_handle(status);
+	}
+	link = link->next;
+    }
+    link = end_procs;
+    while (link != save) {
+	rb_protect((VALUE(*)())link->func, link->data, &status);
 	if (status) {
 	    error_handle(status);
 	}
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 8974096bbc..e1f84376aa 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -849,9 +849,11 @@ open_inet(class, remote_host, remote_serv, local_host, local_serv, type)
 	    continue;
 	}
 	if (type == INET_SERVER) {
+#ifndef NT
 	    status = 1;
 	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
 		       (char*)&status, sizeof(status));
+#endif
 	    status = bind(fd, res->ai_addr, res->ai_addrlen);
 	    syscall = "bind(2)";
 	}
diff --git a/ext/tcltklib/tcltklib.c b/ext/tcltklib/tcltklib.c
index 6c95b42b37..e9c2b56fc1 100644
--- a/ext/tcltklib/tcltklib.c
+++ b/ext/tcltklib/tcltklib.c
@@ -157,7 +157,9 @@ ip_ruby(clientData, interp, argc, argv)
     DUMP2("rb_eval_string(%s)", arg);
     old_trapflg = rb_trap_immediate;
     rb_trap_immediate = 0;
-    res = rb_rescue(rb_eval_string, (VALUE)arg, ip_eval_rescue, (VALUE)&failed);
+    res = rb_rescue2(rb_eval_string, (VALUE)arg,
+                     ip_eval_rescue, (VALUE)&failed,
+                     rb_eStandardError, rb_eScriptError, 0);
     rb_trap_immediate = old_trapflg;
 
     Tcl_ResetResult(interp);
diff --git a/ext/tk/lib/tk.rb b/ext/tk/lib/tk.rb
index e64a6b3af7..967d185053 100644
--- a/ext/tk/lib/tk.rb
+++ b/ext/tk/lib/tk.rb
@@ -77,6 +77,9 @@ module TkComm
   def tk_split_list(str)
     return [] if str == ""
     idx = str.index('{')
+    while idx and idx > 0 and str[idx-1] == ?\\
+      idx = str.index('{', idx+1)
+    end
     return tk_tcl2ruby(str) unless idx
 
     list = tk_tcl2ruby(str[0,idx])
@@ -90,6 +93,7 @@ module TkComm
       brace -= 1 if c == ?}
       break if brace == 0
     }
+    p str[0,i]
     if str[0, i] == ' '
       list.push ' '
     else
@@ -102,6 +106,9 @@ module TkComm
   def tk_split_simplelist(str)
     return [] if str == ""
     idx = str.index('{')
+    while idx and idx > 0 and str[idx-1] == ?\\
+      idx = str.index('{', idx+1)
+    end
     return str.split unless idx
 
     list = str[0,idx].split
@@ -467,7 +474,15 @@ module TkCore
 
   INTERP = TclTkIp.new
 
-  INTERP._invoke("proc", "rb_out", "args", "if {[set st [catch {ruby [format \"TkCore.callback %%Q!%s!\" $args]} ret]] != 0} {if {[regsub -all {!} $args {\\!} newargs] == 0} {return -code $st $ret} {if {[set st [catch {ruby [format \"TkCore.callback %%Q!%s!\" $newargs]} ret]] != 0} {return -code $st $ret} {return $ret}}} {return $ret}")
+  INTERP._invoke("proc", "rb_out", "args", <<-'EOL')
+    regsub -all {!} $args {\\!} args
+    regsub -all "{" $args "\\{" args
+    if {[set st [catch {ruby [format "TkCore.callback %%Q!%s!" $args]} ret]] != 0} {
+	return -code $st $ret
+    } {
+	return $ret
+    }
+  EOL
 
   def callback_break
     fail TkCallbackBreak, "Tk callback returns 'break' status"
diff --git a/file.c b/file.c
index c5d41d2f66..9f44028a2a 100644
--- a/file.c
+++ b/file.c
@@ -143,14 +143,17 @@ static VALUE
 rb_stat_cmp(self, other)
     VALUE self, other;
 {
-    time_t t1 = get_stat(self)->st_mtime;
-    time_t t2 = get_stat(other)->st_mtime;
-    if (t1 == t2)
-	return INT2FIX(0);
-    else if (t1 < t2)
-	return INT2FIX(-1);
-    else
-	return INT2FIX(1);
+    if (rb_obj_is_kind_of(other, rb_obj_class(self))) {
+	time_t t1 = get_stat(self)->st_mtime;
+	time_t t2 = get_stat(other)->st_mtime;
+	if (t1 == t2)
+	    return INT2FIX(0);
+	else if (t1 < t2)
+	    return INT2FIX(-1);
+	else
+	    return INT2FIX(1);
+    }
+    rb_raise(rb_eTypeError, "operand is not File::Stat");
 }
 
 static VALUE
@@ -2492,18 +2495,18 @@ Init_File()
     rb_define_singleton_method(rb_cFile, "basename", rb_file_s_basename, -1);
     rb_define_singleton_method(rb_cFile, "dirname", rb_file_s_dirname, 1);
 
-    separator = rb_str_new2("/");
+    separator = rb_obj_freeze(rb_str_new2("/"));
     rb_define_const(rb_cFile, "Separator", separator);
     rb_define_const(rb_cFile, "SEPARATOR", separator);
     rb_define_singleton_method(rb_cFile, "split",  rb_file_s_split, 1);
     rb_define_singleton_method(rb_cFile, "join",   rb_file_s_join, -2);
 
 #if defined DOSISH && !defined __CYGWIN__
-    rb_define_const(rb_cFile, "ALT_SEPARATOR", rb_str_new2("\\"));
+    rb_define_const(rb_cFile, "ALT_SEPARATOR", rb_obj_freeze(rb_str_new2("\\")));
 #else
     rb_define_const(rb_cFile, "ALT_SEPARATOR", Qnil);
 #endif
-    rb_define_const(rb_cFile, "PATH_SEPARATOR", rb_str_new2(PATH_SEP));
+    rb_define_const(rb_cFile, "PATH_SEPARATOR", rb_obj_freeze(rb_str_new2(PATH_SEP)));
 
     rb_define_method(rb_cIO, "stat",  rb_io_stat, 0); /* this is IO's method */
     rb_define_method(rb_cFile, "lstat",  rb_file_lstat, 0);
diff --git a/hash.c b/hash.c
index 2f9511a8c9..7eb519b8b2 100644
--- a/hash.c
+++ b/hash.c
@@ -1098,7 +1098,7 @@ ruby_unsetenv(name)
 }
 
 static VALUE
-rb_f_setenv(obj, nm, val)
+env_aset(obj, nm, val)
     VALUE obj, nm, val;
 {
     char *name, *value;
@@ -1126,13 +1126,13 @@ rb_f_setenv(obj, nm, val)
 	if (OBJ_TAINTED(val)) {
 	    /* already tainted, no check */
 	    path_tainted = 1;
-	    return Qtrue;
+	    return val;
 	}
 	else {
 	    path_tainted_p(value);
 	}
     }
-    return Qtrue;
+    return val;
 }
 
 static VALUE
@@ -1499,8 +1499,8 @@ Init_Hash()
 
     rb_define_singleton_method(envtbl,"[]", rb_f_getenv, 1);
     rb_define_singleton_method(envtbl,"fetch", env_fetch, -1);
-    rb_define_singleton_method(envtbl,"[]=", rb_f_setenv, 2);
-    rb_define_singleton_method(envtbl,"store", rb_f_setenv, 2);
+    rb_define_singleton_method(envtbl,"[]=", env_aset, 2);
+    rb_define_singleton_method(envtbl,"store", env_aset, 2);
     rb_define_singleton_method(envtbl,"each", env_each, 0);
     rb_define_singleton_method(envtbl,"each_pair", env_each, 0);
     rb_define_singleton_method(envtbl,"each_key", env_each_key, 0);
diff --git a/intern.h b/intern.h
index dd62aed53a..21776fe213 100644
--- a/intern.h
+++ b/intern.h
@@ -50,7 +50,7 @@ VALUE rb_ary_assoc _((VALUE, VALUE));
 VALUE rb_ary_rassoc _((VALUE, VALUE));
 VALUE rb_ary_includes _((VALUE, VALUE));
 VALUE rb_ary_cmp _((VALUE, VALUE));
-VALUE rb_protect_inspect _((VALUE(*)(),VALUE,VALUE));
+VALUE rb_protect_inspect _((VALUE(*)(VALUE,VALUE),VALUE,VALUE));
 VALUE rb_inspecting_p _((VALUE));
 /* bignum.c */
 VALUE rb_big_clone _((VALUE));
diff --git a/io.c b/io.c
index 8d75c291f5..7dd1f493e0 100644
--- a/io.c
+++ b/io.c
@@ -3531,7 +3531,8 @@ Init_IO()
     rb_output_fs = Qnil;
     rb_define_hooked_variable("$,", &rb_output_fs, 0, rb_str_setter);
 
-    rb_rs = rb_default_rs = rb_str_new2("\n"); rb_output_rs = Qnil;
+    rb_rs = rb_default_rs = rb_str_new2("\n");
+    rb_output_rs = Qnil;
     rb_global_variable(&rb_default_rs);
     OBJ_FREEZE(rb_default_rs);	/* avoid modifying RS_default */
     rb_define_variable("$/", &rb_rs);
diff --git a/lib/tracer.rb b/lib/tracer.rb
index 54179dd193..dbe18eacc2 100644
--- a/lib/tracer.rb
+++ b/lib/tracer.rb
@@ -17,12 +17,12 @@ class Tracer
   @RCS_ID='-$Id: tracer.rb,v 1.8 1998/05/19 03:42:49 keiju Exp keiju $-'
 
   @stdout = STDOUT
+  @verbose = false
   class << self
     attr :verbose, true
     alias verbose? verbose
     attr :stdout, true
   end
-  verbose = true
   
   MY_FILE_NAME = caller(0)[0].scan(/^(.*):[0-9]+$/)[0][0]
   
@@ -155,7 +155,7 @@ class Tracer
   
 end
 
-LINES__ = {} unless defined? LINES__
+SCRIPT_LINES__ = {} unless defined? SCRIPT_LINES__
 
 if caller(0).size == 1
   if $0 == Tracer::MY_FILE_NAME
diff --git a/numeric.c b/numeric.c
index 4f11fceec3..5fb67f3390 100644
--- a/numeric.c
+++ b/numeric.c
@@ -153,10 +153,11 @@ num_remainder(x, y)
 {
     VALUE z = rb_funcall(x, '%', 1, y);
 
-    if ((RTEST(rb_funcall(x, '<', 1, INT2FIX(0))) &&
-	 RTEST(rb_funcall(y, '>', 1, INT2FIX(0)))) ||
-	(RTEST(rb_funcall(x, '>', 1, INT2FIX(0))) &&
-	 RTEST(rb_funcall(y, '<', 1, INT2FIX(0))))) {
+    if ((!RTEST(rb_equal(z, INT2FIX(0)))) &&
+	((RTEST(rb_funcall(x, '<', 1, INT2FIX(0))) &&
+	  RTEST(rb_funcall(y, '>', 1, INT2FIX(0)))) ||
+	 (RTEST(rb_funcall(x, '>', 1, INT2FIX(0))) &&
+	  RTEST(rb_funcall(y, '<', 1, INT2FIX(0)))))) {
 	return rb_funcall(z, '-', 1, y);
     }
     return z;
@@ -1310,15 +1311,22 @@ fix_aref(fix, idx)
     VALUE fix, idx;
 {
     long val = FIX2LONG(fix);
-    int i = NUM2INT(idx);
 
-    if (i < 0 || sizeof(VALUE)*CHAR_BIT-1 < i) {
-	if (val < 0) return INT2FIX(1);
+    if (TYPE(idx) == T_BIGNUM) {
+	if (val >= 0) return INT2FIX(0);
+	return INT2FIX(1);
+    }
+    else {
+	int i = NUM2INT(idx);
+
+	if (i < 0 || sizeof(VALUE)*CHAR_BIT-1 < i) {
+	    if (val < 0) return INT2FIX(1);
+	    return INT2FIX(0);
+	}
+	if (val & (1L<<i))
+	    return INT2FIX(1);
 	return INT2FIX(0);
     }
-    if (val & (1L<<i))
-	return INT2FIX(1);
-    return INT2FIX(0);
 }
 
 static VALUE
diff --git a/parse.y b/parse.y
index b1147fc97d..ac26a01577 100644
--- a/parse.y
+++ b/parse.y
@@ -3847,6 +3847,12 @@ str_extend(list, term)
 	    tokadd(c);
 	    goto fetch_id;
 
+	  case '-':
+	    tokadd(c);
+	    c = nextc();
+	    tokadd(c);
+	    goto fetch_id;
+
           default:
 	    if (c == term) {
 		list_append(list, NEW_STR(rb_str_new2("#$")));
diff --git a/ruby.h b/ruby.h
index a2d7f981da..3f6742deea 100644
--- a/ruby.h
+++ b/ruby.h
@@ -488,7 +488,7 @@ void rb_warn __((const char*, ...));		/* reports always */
 VALUE rb_each _((VALUE));
 VALUE rb_yield _((VALUE));
 int rb_block_given_p _((void));
-VALUE rb_iterate _((VALUE(*)(ANYARGS),VALUE,VALUE(*)(ANYARGS),VALUE));
+VALUE rb_iterate _((VALUE(*)(VALUE),VALUE,VALUE(*)(ANYARGS),VALUE));
 VALUE rb_rescue _((VALUE(*)(ANYARGS),VALUE,VALUE(*)(ANYARGS),VALUE));
 VALUE rb_rescue2 __((VALUE(*)(ANYARGS),VALUE,VALUE(*)(ANYARGS),VALUE,...));
 VALUE rb_ensure _((VALUE(*)(ANYARGS),VALUE,VALUE(*)(ANYARGS),VALUE));
diff --git a/time.c b/time.c
index ff52fdc578..e01f99fca5 100644
--- a/time.c
+++ b/time.c
@@ -706,10 +706,10 @@ time_localtime(time)
     time_t t;
 
     GetTimeval(time, tobj);
-    if (tobj->tm_got && !tobj->gmt) {
-	return time;
+    if (tobj->tm_got) {
+	if (!tobj->gmt) return time;
+	time_modify(time);
     }
-    time_modify(time);
     t = tobj->tv.tv_sec;
     tm_tmp = localtime(&t);
     tobj->tm = *tm_tmp;
@@ -727,10 +727,10 @@ time_gmtime(time)
     time_t t;
 
     GetTimeval(time, tobj);
-    if (tobj->tm_got && tobj->gmt) {
-	return time;
+    if (tobj->tm_got) {
+	if (tobj->gmt) return time;
+	time_modify(time);
     }
-    time_modify(time);
     t = tobj->tv.tv_sec;
     tm_tmp = gmtime(&t);
     tobj->tm = *tm_tmp;
diff --git a/variable.c b/variable.c
index bf2c2c918d..fc02f749f7 100644
--- a/variable.c
+++ b/variable.c
@@ -1425,11 +1425,12 @@ cvar_override_check(id, a, b)
 {
     a = RCLASS(a)->super;
     while (a) {
-	if (!RCLASS(a)->iv_tbl) continue;
-	if (st_lookup(RCLASS(a)->iv_tbl,id,0)) {
-	    rb_warning("class variable %s of %s is overridden by %s",
-		       rb_id2name(id), rb_class2name(a),
-		       rb_class2name(b));
+	if (RCLASS(a)->iv_tbl) {
+	    if (st_lookup(RCLASS(a)->iv_tbl,id,0)) {
+		rb_warning("class variable %s of %s is overridden by %s",
+			   rb_id2name(id), rb_class2name(a),
+			   rb_class2name(b));
+	    }
 	}
 	a = RCLASS(a)->super;
     }
@@ -1445,15 +1446,16 @@ rb_cvar_set(klass, id, val)
 
     tmp = klass;
     while (tmp) {
-	if (!RCLASS(tmp)->iv_tbl) continue;
-	if (st_lookup(RCLASS(tmp)->iv_tbl,id,0)) {
-	    if (!OBJ_TAINTED(tmp) && rb_safe_level() >= 4)
-		rb_raise(rb_eSecurityError, "Insecure: can't modify class variable");
-	    st_insert(RCLASS(tmp)->iv_tbl,id,val);
-	    if (ruby_verbose) {
-		cvar_override_check(id, tmp, klass);
+	if (RCLASS(tmp)->iv_tbl) {
+	    if (st_lookup(RCLASS(tmp)->iv_tbl,id,0)) {
+		if (!OBJ_TAINTED(tmp) && rb_safe_level() >= 4)
+		    rb_raise(rb_eSecurityError, "Insecure: can't modify class variable");
+		st_insert(RCLASS(tmp)->iv_tbl,id,val);
+		if (ruby_verbose) {
+		    cvar_override_check(id, tmp, klass);
+		}
+		return;
 	    }
-	    return;
 	}
 	tmp = RCLASS(tmp)->super;
     }
@@ -1500,12 +1502,13 @@ rb_cvar_get(klass, id)
 
     tmp = klass;
     while (tmp) {
-	if (!RCLASS(tmp)->iv_tbl) continue;
-	if (st_lookup(RCLASS(tmp)->iv_tbl,id,&value)) {
-	    if (ruby_verbose) {
-		cvar_override_check(id, tmp, klass);
+	if (RCLASS(tmp)->iv_tbl) {
+	    if (st_lookup(RCLASS(tmp)->iv_tbl,id,&value)) {
+		if (ruby_verbose) {
+		    cvar_override_check(id, tmp, klass);
+		}
+		return value;
 	    }
-	    return value;
 	}
 	tmp = RCLASS(tmp)->super;
     }
diff --git a/version.c b/version.c
index 09569e9d7b..838266dacb 100644
--- a/version.c
+++ b/version.c
@@ -17,9 +17,9 @@
 void
 Init_version()
 {
-    VALUE v = rb_str_new2(RUBY_VERSION);
-    VALUE d = rb_str_new2(RUBY_RELEASE_DATE);
-    VALUE p = rb_str_new2(RUBY_PLATFORM);
+    VALUE v = rb_obj_freeze(rb_str_new2(RUBY_VERSION));
+    VALUE d = rb_obj_freeze(rb_str_new2(RUBY_RELEASE_DATE));
+    VALUE p = rb_obj_freeze(rb_str_new2(RUBY_PLATFORM));
 
     rb_define_global_const("RUBY_VERSION", v);
     rb_define_global_const("RUBY_RELEASE_DATE", d);
diff --git a/version.h b/version.h
index ca6169e60b..ec9deda4e3 100644
--- a/version.h
+++ b/version.h
@@ -1,4 +1,4 @@
 #define RUBY_VERSION "1.7.1"
-#define RUBY_RELEASE_DATE "2001-10-22"
+#define RUBY_RELEASE_DATE "2001-10-29"
 #define RUBY_VERSION_CODE 171
-#define RUBY_RELEASE_CODE 20011022
+#define RUBY_RELEASE_CODE 20011029