Re: ANN: Ada 2005 Math Extensions 20120712

[Simon Wright <simon@pushface.org>]

Ada novice <shai.lesh@gmx.com> writes:

> After knowing that the lapack and blas libraries are functional on my
> linux system, I tried the new math extension package. I do not
> understand however how lapack and blas are called.
>
> After issuing the command: $ gnatmake -p -P demo_extensions, I see
> further down the output these lines:
>
> gnatbind -E -I- -x /home/work/ada/simon2012/test/.build/demo_extensions.ali
> gnatlink /home/work/ada/simon2012/test/.build/demo_extensions.ali -g
> /home/work/ada/simon2012/lib/libgnat_math_extensions.a
> -Wl,-rpath,/usr/local/gnat-2012/lib/gcc/i686-pc-linux-gnu/4.5.4/adalib/
> -llapack -lblas -o
>
> So the linker is calling -llpack and -lblas. 
>
> When I execute $ ./demo_extensions, I do get a long list of outputs
[...]
> as expected from the code
>
> My question is at which stage -llpack and -lblas are called? The file
> demo_extensions.gpr does not have these "switches" in the linker
> section.

demo_extensions.gpr starts

   with "../gnat_math_extensions";

and gnat_math_extensions.gpr contains

   package Linker is
      for Linker_Options use ("-llapack", "-lblas");
   end Linker;

> I would like to know what lapack and blas libraries are being called,
> and if I can switch to the ACML ones which also work well for other
> Ada programs.

"ldd demo_extensions" will show you which shareable libraries are used
by the executable demo_extensions.

You should be able to switch to the ACML libraries without trouble. You
may be able to do so without re-linking; I don't remember how to do that
(setting the env var LD_PRELOAD to the replacement libraries??)