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Re: PATCH: arm*-*-symbianelf* tests


On Tue, Aug 03, 2004 at 02:44:31PM -0700, Andrew Pinski wrote:
> 
> On Aug 3, 2004, at 2:40 PM, Mark Mitchell wrote:
> >See this comment in config/arm/symbian.h:
> >
> >/* Do not expand builtin functions (unless explicitly prefixed with
> >  "__builtin").  Symbian OS code relies on properties of the standard
> >  library that go beyond those guaranteed by the ANSI/ISO standard.
> >  For example, "memcpy" works even with overlapping memory, like
> >  "memmove".  */
> 
> 
> But that guaranteed is above and beyond the ISO C standard and should 
> not
> be enough to disable builtins as Darwin really has the same thing in 
> that memcpy
> and memmove are really the same function.

That's not the same thing.  What you're talking about is a behavior of
the implementation that is above and beyond the standard.  What Symbian
has (if I'm understanding Mark right) is a specification above and
beyond the standard.  So on Symbian OS, it will be legal to call memcpy
from user code which knows the two regions overlap.  But GCC's inline
expansion of memcpy may make the valid ISO C assumption that this is
not the case.

-- 
Daniel Jacobowitz


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