Re: ix86 targets without BFD64

["Jan Beulich" <JBeulich at suse dot com>]

>>> 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?

Jan