[Bug middle-end/57748] [4.8/4.9 Regression] ICE on ARM with -mfloat-abi=softfp -mfpu=neon

[jamborm at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57748

--- Comment #11 from Martin Jambor <jamborm at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #8)
> (In reply to Martin Jambor from comment #7)
> > In any event, it is clear that
> > the code in expand_assignment cannot cope with unaligned tem and non-NULL
> > offset.  So currently I'm considering the following patch, although I am not
> > really sure it is enough (it does fix the ICE, though).  If you can run the
> > testcase on the platform, would you run it with this patch applied, please?
> 
> No, unfortunately I can only look at the assembler listing.
> 
> But wait a moment...
> 
> If the object is assumed to be unaligned here this patch will
> likely just compute the unaligned address, add the offset,
> and store the result there without any special precautions.
> While the code in the if statement seems to store the expression
> on a register and move that register to the final destination.
> 
> Well, I believe this unaligned arrays are generally broken.
> 
> consider this example:

With or without the patch?  If without the patch and you are
reasonably confident the output is indeed wrong, please open a new PR
(and CC me, I'm interested) because this particular ICE is certainly
caused by trailing zero sized arrays.  I have tried reproducing your
problem with x86_64 MMX vectors but couldn't.  I do not have access to
an ARM machine to verify myself.  Thanks.