[LLVMdev] troubles with llvm-gcc 4.0 and APFloat on X86_64

[Dale Johannesen]

On Oct 22, 2007, at 2:08 AM, Dietmar Ebner wrote:

> hi,
>
> i've got some more things to note. first, the issue is not related to
> x86_64 being the host machine - it also happens on i686/linux.
>
> next, i think (one of) the problem(s) is the use of
> [HOST_]WORDS_BIG_ENDIAN instead of [HOST_]FLOAT_WORDS_BIG_ENDIAN in
> llvm-convert.cpp (see patch below).
>
> this fixes single precision floating point but breaks double  
> precision.
> for arm-softfloat-linux-gnu, FLOAT_WORDS_BIG_ENDIAN is true while
> WORDS_BIG_ENDIAN is false. as far as i've seen, there's only a single
> flag for endianess in the llvm target description string, so i don't
> really understand how this is supposed to work.

Agree.  I think those two match on all the targets I've tried.

I think the right approach is to use REAL_VALUE_TO_TARGET_SINGLE for  
float
and REAL_VALUE_TO_TARGET_DOUBLE for double, then the two endiannesses
can be handled separately.

> i wonder how other people are cross compiling for arm-linux-gnu?
> any help would be highly appreciated!