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Subject: Re: clang 3.2 RC2 miscompiles libgcc?
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From: David Chisnall <theraven@freebsd.org>
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To: Dimitry Andric <dim@freebsd.org>
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On 7 Jan 2013, at 23:21, Dimitry Andric wrote:

> This is at least the direction I'm looking at.  It seems that in some
> cases with __builtin_eh_return(), llvm does not see that registers can
> be clobbered, and it doesn't save and restore them.

Do you mean that some registers were clobbered by a prior call?  =
__builtin_eh_return() doesn't return, so whether it clobbers anything or =
not isn't something that should matter.  The preceding call is =
__builtin_frob_return_addr, which seems to be a no-op, so it shouldn't =
clobber any registers either...

David=