From: Eric Wong <normalperson@...>
Date: 2011-06-11T03:15:47+09:00
Subject: [ruby-core:36948] Re: rb_str_modify() now required before rb_str_resize()?

SASADA Koichi <ko1@atdot.net> wrote:
> (2011/05/01 11:48), Eric Wong wrote:
> > In 1.9.2 and earlier, rb_str_resize() always calls rb_str_modify()
> > internally.  Some C extensions I maintain relied on this behavior.
> > 
> > In trunk, rb_str_resize() no longer calls rb_str_modify() nor unshares
> > the string for copy-on-write if the string is already the desired size.
> > 
> > I believe this is inconsistent since a C extension would normally expect
> > to write to a string (and thus need to trigger copy-on-write) if it's
> > calling rb_str_resize() on it.
> 
> It seems that there are no discussion about this topic.  Who change it?

I think this is from r28827, so nobu.

> In my opinion, I can't imagine that rb_str_resize() always call
> rb_str_modify().

OK.  I've modified all my C extensions to call rb_str_modify() already.
MRI sources itself calls rb_str_modify() before rb_str_resize(), too.
Maybe there are other C extensions affected?

-- 
Eric Wong