Re: cross-compiling pari for Android

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Thu, Jul 21, 2011 at 03:17:23PM -0400, Charles Boyd wrote:
> Hi,
> 
> I am trying to port PARI/GP to Android by cross compiling with the
> standalone NDK toolchain (contains system headers, libs, C compiler, etc).
> 
> The way I am trying to do this is by writing a simple shell script which
> exports the C compiler (et. all) and points to the appropriate Android
> headers and invokes the usual Configure script after all of the
> Android-specific things are taken care of.
> 
> There is a problem I keep running into with the Configure script, which
> immediately tries to compile and run the ansi.c program -- the build
> obviously fails since I am compiling for the arm-linux-androideabi target,
> but working on a Linux-x86 host.
> 
> This leads me to a few questions:
> 
> (1) Is there any simple way to invoke the Configure script without
> performing the tests?

./Configure -a

> If not, how does the Configure script expect me to run
> ARM binaries on an x86 machine? 

By using an emulator (e.g. qemu-arm) and the environment variable 
RUNTEST.

> I just want to build libpari.so such that it
> can be invoked by a test C program on an ARM device running Android. I'm not
> worrying about GP or readline or anything else right now. The first step is
> getting only the library to compile.
>
> (2) Instead of writing a wrapper script for the Android port around the
> existing Configure script, should I modify the Configure script to work for
> Android? I don't mind getting my hands dirty, but this seems like an
> error-prone and time consuming way to do something relatively simple.

You just need to create a pari.cfg file with ./Configure -a and then do
./Configure -l pari.cfg 

> There is apparently an existing ARM port for PARI/GP in the Debian
> repository. How did they do this? Compiled directly on the ARM device?

PARI/GP for ARM is compiled natively. 

Cheers,
Bill.