Re: libstdc++/52: can't call c_str() from a basic_string<unsigned char> (fwd)

[Benjamin Kosnik <bkoz at cygnus dot com>]

The following reply was made to PR libstdc++/52; it has been noted by GNATS.

From: Benjamin Kosnik <bkoz@cygnus.com>
To: libstdc++-gnats@sourceware.cygnus.com
Cc:  
Subject: Re: libstdc++/52: can't call c_str() from a basic_string<unsigned char> (fwd)
Date: Fri, 31 Mar 2000 11:39:43 -0800 (PST)

 ---------- Forwarded message ----------
 Date: Thu, 30 Mar 2000 14:35:27 -0800
 From: ncm@zembu.com
 To: bkoz@cygnus.com
 Subject: Re: libstdc++/52: can't call c_str() from a basic_string<unsigned char>
 
 > >Number:         52
 > >Category:       libstdc++
 > >Synopsis:       can't call c_str() from a basic_string<unsigned char>
 > >Confidential:   no
 > >Severity:       serious
 > >Priority:       medium
 > >Responsible:    unassigned
 > >State:          open
 > >Class:          sw-bug
 > >Submitter-Id:   net
 > >Arrival-Date:   Thu Mar 30 12:27:00 PST 2000
 > >Closed-Date:
 > >Last-Modified:
 > >Originator:     debian frozen
 > >Release:        ibstdc++2.10-dev    2.95.2-8
 > >Organization:
 > >Environment:
 > debian frozen
 > >Description:
 > The problem is that "" is a signed char * and so when it is 
 > assigned to charT* there is no problem as long as charT* 
 > is a signed char. The problem is if instantiate a basic 
 > string with an unsigned char rather than a char this doesn't
 > work. I don't know how this will behave with multibyte 
 > characters.
 > >How-To-Repeat:
 > 
 > >Fix:
 > RCS file: RCS/bastring.h,v
 > retrieving revision 1.1
 > diff -u -r1.1 bastring.h
 > --- bastring.h	2000/03/30 00:44:05	1.1
 > +++ bastring.h	2000/03/30 00:46:05
 > @@ -335,7 +335,7 @@
 >  
 >  public:
 >    const charT* c_str () const
 > -    { const charT* null_str = ""; 
 > +    { const charT* null_str = reinterpret_cast<const charT*>(""); 
 >        if (length () == 0) return null_str; terminate (); return data (); }
 >    void resize (size_type n, charT c);
 >    void resize (size_type n)
 
 I don't agree with this change.  A better fix would be:
 
 > +    { static const charT null_str[] = { charT() };
 
 Of course, since this is the old, dead libstdc++, I don't care what
 happens there.
 
 Nathan
 ncm