[Bug jit/64810] jit not working on armv7hl ("ld: error: /tmp/libgccjit-ZGemdr/fake.so uses VFP register arguments, /tmp/ccJFCBsE.o does not")

[ramana.radhakrishnan at arm dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64810

--- Comment #8 from ramana.radhakrishnan at arm dot com <ramana.radhakrishnan at arm dot com> ---
On 27/01/15 20:00, dmalcolm at gcc dot gnu.org wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64810
>
> --- Comment #7 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
> (In reply to ramana.radhakrishnan@arm.com from comment #4)
>> On 27/01/15 12:27, jakub at gcc dot gnu.org wrote:
>>> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64810
>>>
>>> Jakub Jelinek <jakub at gcc dot gnu.org> changed:
>>>
>>>              What    |Removed                     |Added
>>> ----------------------------------------------------------------------------
>>>                    CC|                            |jakub at gcc dot gnu.org
>>>
>>> --- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
>>> Both the compiler and libgccjit were configured with:
>>> --with-tune=cortex-a8 --with-arch=armv7-a --with-float=hard
>>> --with-fpu=vfpv3-d16 --with-abi=aapcs-linux
>>
>>
>> The --with-abi=aapcs-linux in addition to the --with-float=hard argument
>> is just wrong. In fact it allows for a case where if the order of
>> command line arguments passed to the compiler if in some way is wrong,
>> the code generated will force the compiler into passing floating point
>> parameters through the integer registers rather than fp registers which
>> is what the --with-float=hard configure time option is doing.
>>
>> Really Fedora should remove this from the configure line as it only
>> confuses people.
>
> Ramana: I'm sorry, I had trouble parsing your comment (e.g. which option were
> you referring to by "this" in the final sentence above).


By "this" in the final sentence, I referred to the 
--with-abi=aapcs-linux option.


>
> What should I configure with when debugging this?
> e.g. should I keep the --with-abi=aapcs-linux and lose the --with-float=hard?
> should I be testing with the other options Jakub mentioned?  etc.

The architecture specific options that are commonly used for 
bootstrapping on ARM hard float are the following.

--with-arch=armv7-a --with-float=hard --with-fpu=vfpv3-d16


>
> (Sorry about my ignorance here; I'm not particularly familiar with arm, and my
> test machine is slow which makes it difficult to exhaustively try every
> possibility).

No problem it's not an issue - there are quite a few options available 
so it's not easy to get the correct options sorted in the first instance.


Ramana
>