Configure fails on 32-bit platform

Vincent Lefevre vincent at
Mon Feb 12 10:25:49 UTC 2018

On 2018-02-12 10:31:23 +0100, Torbjorn Granlund wrote:
> Vincent Lefevre <vincent at> writes:
>   As written above, this is for C compilers. But GMP also has assembler
>   code. So, you need to provide an option that will affect the assembler
>   code. This is what ABI is for.
>   That said, perhaps GMP might be improved to detect the ABI by a
>   simple parsing of $CFLAGS when provided by the user (in case values
>   like -m32 or -m64 are standard). The reason is that the user could
>   have a generic CFLAGS for various software, while AFAIK, ABI is
>   specific to GMP.
> That would be nice but unfortunately is not going to work.
> We use "ABI" in a somewhat non-standard way.  It mainly refers to the
> limb size.  The same exact compiler flags might be correct for several
> choices of "ABI".

So, if I understand correctly, this means that if the user chooses
to set -m32 in CFLAGS, he might have to try different ABI values
before finding one that works (because -m32 does not necessarily
imply 32-bit limbs). This is not nice.

Vincent Lefèvre <vincent at> - Web: <>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)

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