GNU make is required for compilation.

Libsharp compilation has been successfully tested with GNU and Intel compilers.
When using gcc, version 4.x is required [1].
Since libsharp was written in standard C99, other compilers should work fine,
but SSE2/AVX support will most likely be deactivated.

If you obtained libsharp directly from the git repository, you will also
need a copy of the GNU autotools. In this case, run "autoconf" in libsharp's
main directory before any other steps.
For libsharp releases distributed as a .tar.gz file, this step is not necessary.

Afterwards, simply run "./configure"; if this fails, please refer to the output
of "./configure --help" for additional hints and, if necessary, provide
additional flags to the configure script.
Once the script finishes successfully, run "make"
(or "gmake"). This should install the compilation products in the
subdirectory "auto/".

Documentation can be created by the command "(g)make doc".
However this requires the doxygen application to be installed
on your system.
The documentation will be created in the subdirectory doc/.


[1] Some versions of the gcc 4.4.x release series contain a bug which causes
the compiler to crash during libsharp compilation. This appears to be fixed
in the gcc 4.4.7 release. It is possible to work around this problem by adding
the compiler flag "-fno-tree-fre" after the other optimization flags - the
configure script should do this automatically.