Jakub Jelinek <jakub at gcc dot> changed:

           What    |Removed                     |Added
                 CC|                            |jakub at gcc dot

--- Comment #2 from Jakub Jelinek <jakub at gcc dot> ---
On some targets where the address spaces are really separate, one kind of
memory and another kind of memory, I can see why assuming non-aliasing is fine.
But exactly on x86_64 I don't see how that could be safe, %fs/%gs simply are
the given addresses plus the segment base.  You can access the same memory both
%gs:ptr1 and ptr2 where ptr2 is ptr1 + gs_segment_base, e.g. glibc uses for TLS
heavily both kinds of accesses.

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