ix86 targets without BFD64

[H.J. Lu]

On Mon, Oct 23, 2017 at 5:22 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Mon, Oct 23, 2017 at 5:11 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>>> On 23.10.17 at 13:13, <hjl.tools@gmail.com> wrote:
>>> On Sun, Oct 22, 2017 at 11:53 PM, Jan Beulich <JBeulich@suse.com> wrote:
>>>> Hello,
>>>>
>>>> there being quite a few BFD64 conditionals in tc-i386.c, I would
>>>> conclude that things are supposed to work fine when doing a
>>>> purely 32-bit build (which happen to result when I cross build on
>>>> cygwin, but of course by not forcing --enable-64-bit-bfd I can
>>>> also see this on a native Linux build on a 32-bit distro). Yet each of
>>>> the last two lines of
>>>>
>>>>         .text
>>>> _start:
>>>>         mov     0x87654321, %eax
>>>>         mov     $0x87654321, %eax
>>>>
>>>>         .code64
>>>>         movabs  0x87654321, %al
>>>>         movabs  $0x87654321, %rax
>>>>
>>>> trigger the abort() in offset_in_range(). Since the chosen target
>>>> automatically enables elf32_x86_64, the solution can't possibly be
>>>> to disallow .code64 in such a build. All other alternatives I can
>>>> think of would, however, appear to require a full audit of all 64-bit
>>>> immediate / displacement processing in order to make sure all valid
>>>> code (i.e. anything not requiring 64-bit relocations) is accepted.
>>>>
>>>> Thoughts?
>>>
>>> We can disable elf32_x86_64 and disallow .code64 if bfd_vma is 32 bit.
>>
>> Hmm, interesting. Then why was it added there in the first place?

elf32_x86_64 is added by

targ_extra_libpath=elf32_x86_64

Since elf64-x86-64.o isn't compiled in, elf32_x86_64 never worked.

>>
>
> Since my i386 binutils is built with 64-bit BFD, it isn't a problem.
> BTW, I don't believe elf32_x86_64 linker works correctly with 32-bit
> BFD.
>

I am going to check in this patch.


-- 
H.J.
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