Re: [patch,lto] Fix PR81487

[Richard Biener <richard dot guenther at gmail dot com>]

On Thu, Jul 20, 2017 at 3:18 PM, Georg-Johann Lay <avr@gjlay.de> wrote:
> Hi, this patch fixes some minor problems in lto-plugin:
>
> Some older mingw32 host environments have broken asprintf.
> As far as I can tell, the problem is that the mingw asprintf
> implementation calls _vsnprintf (NULL, 0, ...) which always
> returns -1 as length on the host.
>
> The patch fixes this by using xasprintf from libiberty with
> the additional benefit of easier use and unified error reporting
> in the case when there is actually no more memory available, i.e.
> it will use the same error massages like xmalloc then.
>
> Moreover, the old implementation calls asprintf as
>
>> asprintf (&objname, "%s@0x%x%08x", file->name, lo, hi)
>
> for large archives when the high 32 bits (hi) are non-zero.
> This looks like a typo: the high part must come first to yiels
> a proper 64-bit value.
>
> Bootstrapped & re-tested on x86_64-linux gnu and also on
> mingw32 which popped the "ld.exe: asprintf failed".
>
> Ok for trunk?

Ok.

I wonder if any of the other plain asprintf calls in GCC are
problematic.  From a quick look they are all inside code
only exercised when dumping/debugging.  But maybe we
should replace those as well.

Richard.

> Johann
>
>
> lto-plugin/
>         PR lto/81487
>         * lto-plugin.c (claim_file_handler): Use xasprintf instead of
>         asprintf.
>         [hi!=0]: Swap hi and lo arguments supplied to xasprintf.