subs_header:
    sed commands used to generate the ba?.h files at build time from 
    the many different small ones. The #include need to be inactivated.
    Some #ifdef are inserted because of some C/C++ incompatibility.

subs_config:
    sed commands used to modify config.h (result in ba0.h).
    The PACKAGE_* macros are suppressed and replaced by BLAD_* ones.

subs_mint_hp:
subs_mpfr:
subs_mpz:
subs_mpq:
subs_mpzm:
    sed commands used while building the bap library in order to generate
    code for many different types of numbers from the generic one.
