Re: [RFA] defs.h: Define GDB_DEFAULT_TARGET_[WIDE_]CHARSET for Cygwin and MingW builds

[Corinna Vinschen <vinschen at redhat dot com>]

On Mar  3 11:41, Corinna Vinschen wrote:
> However, there's a problem in GDB which spoils the effort a bit.
> 
> When GDB is started, setlocale() is called from captured_main().
> Afterwards, _initialize_charset() and, in turn, nl_langinfo() is
> called, and the pointer returned by nl_langinfo(CODESET) is
> stored as the name of the codeset.
> So the codeset name is not copied into a safe storage area here,
> just the pointer is memorized.
> 
> Later, while captured_main() is still initializing GDB, the interp_set()
> function is called, which calls tui_init(), which in turn initializes
> readline.  Readline calls setlocale().  Oops.  The old pointer to
> nl_langinfo(CODESET) might not be valid anymore afterwards.
> 
> See the Linux manpage for nl_langinfo:
> 
>   RETURN VALUE
>     [...]
>     This pointer may point to static data that may be overwritten on the
>     next call to nl_langinfo() or setlocale(3).
> 
> So, does anything speak against copying the codeset name into some
> local storage, rather than just  storing the pointer returned by
> nl_langinfo?

Accidentally omitted from my former mail:

Since nl_langinfo is called only once here anyway, a simple

  auto_host_charset_name = strdup (nl_langinfo (CODESET));

would do.


Corinna

-- 
Corinna Vinschen
Cygwin Project Co-Leader
Red Hat