why Glibc does not build with clang?

[pinskia@gmail.com]

> On May 24, 2014, at 9:11 AM, Andreas Schwab <schwab@linux-m68k.org> wrote:
> 
> Rich Felker <dalias@libc.org> writes:
> 
>>> On Sat, May 24, 2014 at 04:46:03PM +0200, Andreas Schwab wrote:
>>> Rich Felker <dalias@libc.org> writes:
>>> 
>>>> Nested functions are a feature that fundamentally requires producing
>>>> an insecure executable/library (executable-stack flag)
>>> 
>>> Only if you pass the address of it out of the containing function.
>> 
>> That's my "_except_ in cases where the compiler optimizes out that
>> need."
> 
> That's not the exception, that's the rule.  If you never take the
> address of the nested function you never need a trampoline.

Andreas is correct, trampolines are never generated unless you take the address of a nested function. It is not an optimization as it never generated to begin with. Also some abi don't need a trampoline: PPC64v1 for an example. 

Thanks,
Andrew

> 
> Andreas.
> 
> -- 
> Andreas Schwab, schwab@linux-m68k.org
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