From: matz@... (Yukihiro Matsumoto)
Date: 1999-01-18T12:12:05+09:00
Subject: [ruby-talk:00196] Re: defining self causes a segmentation fault

Hi.

In message "[ruby-talk:00191] defining self causes a segmentation fault"
    on 99/01/16, Julian Fondren <julian@imaji.net> writes:

|Hello,
|
|In ruby you can't change the value of self, and I just learned this,
|because of the following:

Yes. The `self' is pseudo variable, which looks like local variable,
but it really is a constant.

|-:1: Can't change the value of self
|self=nil
|     ^
|-:1: [BUG] Segmentation fault
|
|
|which partially explains things. I assume here that this is some kind of
|bug and that ruby isn't supposed to segfault on an attempt to define
|self.. though maybe it is. Also this might be restricted to my machine -
|something I have certainly seen before - or at least the segfault part
|might. Anyway, what's the deal here?

Any SEGV caused by script is supposed to be bug in interpreter or
extension library.  It's a bug.  Here's the patch.

--- parse.y	1998/11/26 08:25:45	1.1.1.2.2.54
+++ parse.y	1999/01/18 02:59:05
@@ -574,4 +574,6 @@
 		        $$ = $<node>3;
+			if ($$) {
 		        $$->nd_value = $4;
 		        fixpos($$, $4);
+			}
 		    }