RE: alloca in HP NonStop

[Joachim Schmitz]

> From: Paul Eggert [mailto:address@hidden
> Sent: Tuesday, July 03, 2012 2:38 AM
> To: Joachim Schmitz
> Cc: address@hidden
> Subject: Re: alloca in HP NonStop
> 
> On 06/28/2012 09:41 AM, Joachim Schmitz wrote:
> > Or drop it an just take the else branch.
>
> Yes, that sounds simpler.  Also, how about the following ideas for 
> simplification:
> 
> Don't bother checking __TANDEM; _TNS_E_TARGET should suffice.
> This fixes what appears to be a bug on older Tandem systems.

Well, rather a missfeature of the older platforms and their compilers to not 
have that builtin _alloca
Our code always check for __TANDEM && _TNS_E_TARGET, I guess that is for a good 
reason, so I'd rather keep that.
Also is is similar to
# elif defined __DECC && defined __VMS

I had my code after that, you placed it before that, any special reason?

> Don't define _BUILTIN (couldn't see why this mattered).

Yes, I had that to prevent <builtin.h> multiple inclusion, but come to think of 
it a check for #ifdef alloca (in our code, it is in GNUlib already) should help 
too.

> Omit most comments (not really needed here; it's pretty explanatory).

Sure, I just had them in to explain why I did what.

> Use GNU style (space before paren) in pragma.

Sure
 
> In short, how about the following patch instead?
> 
> ---
>  ChangeLog       |    7 +++++++
>  lib/alloca.in.h |    7 +++++++
>  2 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/ChangeLog b/ChangeLog
> index e7f7883..979d18a 100644
> --- a/ChangeLog
> +++ b/ChangeLog
> @@ -1,3 +1,10 @@
> +2012-07-02  Paul Eggert  <address@hidden>
> +
> +     alloca: add support for HP NonStop TNS/E native
> +     * lib/alloca.in.h (alloca): Support the new host.
> +     From a suggestion by Joachim Schmitz in
> +     <http://lists.gnu.org/archive/html/bug-gnulib/2012-
> 06/msg00355.html>.
> +
>  2012-07-02  Pádraig Brady  <address@hidden>
> 
>       fsusage: remove code not needed on non GNU/Linux systems.
> diff --git a/lib/alloca.in.h b/lib/alloca.in.h index 99be048..0f5ce34 100644
> --- a/lib/alloca.in.h
> +++ b/lib/alloca.in.h
> @@ -42,6 +42,13 @@
>  # elif defined _MSC_VER
>  #  include <malloc.h>
>  #  define alloca _alloca
> +# elif defined _TNS_E_TARGET /* HP NonStop TNS/E native */ 

Drop the 'native', it is superfluous, on TNS/E we don't have non-native in this 
context
As mentioned above I'd rather add a check for __TANDEM

> +#  ifdef __cplusplus
> +    extern "C"

I' don't quite understand, why not the entire alloca.in.h is bracketed by this.
At least now that it is used in 2 places?

> +#  endif
> +   void *_alloca (unsigned short);
> +#  pragma intrinsic (_alloca)
> +#  define alloca _alloca
>  # elif defined __DECC && defined __VMS
>  #  define alloca __ALLOCA

As the DEC/VMS part seems much simpler, I'd move it above the NonStop part?

>  # else

Bye, Jojo