Bug#684631: clisp doesn't build on armv7 hardware

[martinwguy]

On 12/08/2012, peter green <plugwash at p10link.net> wrote:
> package: clisp
> However the author of the patch claims the patch will
> not work on v4, he is not clear whether when he says v4 he means only
> plain v4 (which debian doesn't support) or whether he also includes v4t
> (which debian does support) in that. Specifically he says
>
>  >After doing that, I again hit an illegal instruction, this time on a
> line of this form:
>  >
>  >MOVEQS pc, lr
>  >
>  >That form of the instruction has been deprecated, and is apparently
> now illegal on whatever Fedora's koji builders use. The new way to do
> that is this:
>  >
>  >BXEQ lr
>  >
>  >which the assembly language reference manual says is also friendlier
> to the branch prediction logic. However, that instruction is not
> available on ARM v4 and earlier. That >doesn't cause me any issues,
> since Fedora only supports ARM v5 and later"
>
> Can any arm assembler experts comment on whether this patch will break
> things on armv4t (i'm pretty sure v4t has plain BX but I dunno about
> BXEQ, a google search doesn't even seem to find anything relavent for
> BXEQ)

The arm assembler reference manual
ddi0100e_arm_arm.pdf, section 4.1.10
says that BX does has a conditional execution field (the EQ) and is
available from arm5 and on T variants of ARM4 so that should work on
Delian armel.

    M