[patch] Reject alias to declarations in ELF and COFF

[Rafael Espíndola]

Since it looks like MachO will be getting support for aliases with
N_INDR, this patch just rejects aliases to declarations on ELF and
COFF.

The use of report_fatal_error is probably OK, since it shows a problem
in the FE producing the alias.  Clang for example rejects this
already.

Another option would be to add target information to the verifier, but
that looks odd.

Cheers,
Rafael
-------------- next part --------------
A non-text attachment was scrubbed...
Name: t.patch
Type: text/x-patch
Size: 8239 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20131031/2da003bf/attachment.bin>