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Re: expanding builtins


Jakub Jelinek <jakub@redhat.com> writes:

> On Mon, Jun 27, 2005 at 10:11:50AM -0400, James Lemke wrote:
>> I have a situation where a structure is not properly aligned and I want
>> to copy it to fix this.
>> 
>> I'm aware that -no-builtin-memcpy will suppress the expansion of
>> memcpy() (force library calls) for a whole module.  Is it possible to
>> suppress the expansion for a single invocation?
>
> You can:
> #include <string.h>
> ...
> extern __typeof(memcpy) my_memcpy __asm ("memcpy");
>
> and use my_memcpy instead of memcpy in the place where you want to force
> library call.

Except that sometimes the function is actually called _memcpy at the
assembler level.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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