Re: [patch][rfc] Allow GDB to search for the right libthread_db.so.1

[Daniel Jacobowitz <drow@false.org>]

I have just a few minor comments on this.  Overall, I am heartily
in favor of the idea - I have carried a less elegant version of this
feature in the Debian GDB packages for two years or so.

On Fri, Apr 17, 2009 at 12:13:08PM -0700, Paul Pluzhnikov wrote:
> +#ifndef LIBTHREAD_DB_SO
> +#define LIBTHREAD_DB_SO "libthread_db.so.1"
> +#endif
> +
> +#ifndef LIBTHREAD_DB_SEARCH_PATH
> +#define LIBTHREAD_DB_SEARCH_PATH ""
> +#endif

Do we intend to let anything override these?  Otherwise IMHO the
ifndef just confuses the issue.

> +static int
> +try_thread_db_load_1(void *handle)

Space before paren :-)

> +  if (info_verbose && strchr(library, '/') == NULL)

Oh, here too.

> +  msym = lookup_minimal_symbol ("nptl_version", NULL, NULL);
> +  if (!msym)
> +    msym = lookup_minimal_symbol ("__linuxthreads_version", NULL, NULL);
> +
> +  /* Some really old libpthread versions do not have either of the above.  */
> +  if (!msym)
> +    msym = lookup_minimal_symbol ("__pthread_threads_events", NULL, NULL);
> +
> +  if (!msym)
> +    /* No threads yet */
> +    return 0;

Why is this symbol lookup necessary?  Is it accomplishing the same
thing that searching for a shared library matching "libpthread[-.]"
would?  Also see libpthread_solib_p, which uses basically that
method.

> +  libthread_db_search_path = xstrdup(LIBTHREAD_DB_SEARCH_PATH);

Space there too :-)

-- 
Daniel Jacobowitz
CodeSourcery