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Re: Fix strict-aliasing warnings from unwind-dw2-fde.c
On Mon, 26 Nov 2012, Roland McGrath wrote:
> > That's the intention of my patch - use memcpy, in an inline function so
> > the compiler can see everything and optimize to the same code as for type
> > punning as appropriate.
>
> Please verify that the change does not change the compiled code for x86-64.
> If it doesn't change the code, or any changes don't reduce performance,
> then this is OK.
This code is not used for x86_64 - it's only used if SHLIB_COMPAT (libc,
GLIBC_2_0, GLIBC_2_2_5).
For 32-bit x86, the only change I see to compiled code is that two
instructions are swapped in the prologue of fde_unencoded_compare.
--
Joseph S. Myers
joseph@codesourcery.com