[PATCH] bfd: Add support for more than one plugin in lib/bfd-plugins

[Alan Modra]

On Tue, Sep 23, 2014 at 08:25:36AM +0200, Markus Trippelsdorf wrote:
> 	PR 17422
> 	* plugin.c (try_claim): New function. Moved from
> 	bfd_plugin_object_p.
> 	(try_load_plugin): Pass though filename. Add test.
> 	(load_plugin): Pass though filename.
> 	(bfd_plugin_object_p): Move logic to try_claim.

I like what you're doing, but there are a few problems.

> +try_load_plugin (const char *pname, bfd *abfd)
>  {
>    static void *plugin_handle;

Nit, preexisting.  Seems to me that this should no longer be a static
var.

>    int tv_size = 4;
> @@ -164,7 +209,6 @@ try_load_plugin (const char *pname)
>    int i;
>    ld_plugin_onload onload;
>    enum ld_plugin_status status;
> -
>    plugin_handle = dlopen (pname, RTLD_NOW);
>    if (!plugin_handle)
>      {
> @@ -200,6 +244,9 @@ try_load_plugin (const char *pname)
>    if (!claim_file)
>      goto err;
>  
> +  if (!try_claim (abfd))
> +    goto err;

Since you're calling try_claim here..

> -  lseek(file.fd, cur_offset, SEEK_SET);
> -  if (!claimed)
> +  if (!try_claim (abfd))
>      return NULL;

..you shouldn't do so here in bfd_plugin_object_p.

A perhaps more serious issue is that after your patch we'll call
dlopen() and onload() on each lto input object file.  Before, we
dlopen a plugin and call onload just once.

-- 
Alan Modra
Australia Development Lab, IBM