[LLVMdev] Linking strncpy

[Reid Spencer]

On Wed, 2004-04-14 at 22:16, Chris Lattner wrote:
> On Wed, 14 Apr 2004, Reid Spencer wrote:
> 
> >
> > > You don't need to do this to get those annoying GCC warnings.  They come
> > > out whenever you compile a C program produced by the LLVM CBE that uses
> > > certain GCC "builtins", like memcpy... :(
> > >
> > > -Chris
> >
> > That's weird. Perhaps GCC knows about its own builtin functions and the
> > prototypes for them so that if you declare a similar function with the
> > wrong prototype you get the warning?
> 
> But it only gives warnings for SOME builtins.  :)  Perhaps -fno-builtins
> will silence the warning.  *shrug*
> 
> -Chris

I would suspect (and this is only a guess) that GCC would warn on
builtins that it doesn't actually generate a function for.
memcpy/memmove fall into this category on processors like i86 because
there are simple instructions to essentially do the copy/move. Even
though the function may be declared and even implemented somewhere in a
header file, it probably singles a few of them out for direct code
implementation rather than function call?

Just a guess.

Reid.
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