Type representing signed size doesn't have to be int, so use special value
which defaults to SSIZE_MAX, but as it's not defined by C standard (but rather
by POSIX), allow ports to set it.
For the sake of older versions of gcc (and other compilers), don't use
the #warning CPP directive, nor the -Wno-error=cpp option.
Also, fix a strict alias warning in modffi.c for older compilers, and
add a test for ffi module.
Addresses issue #847.
Previously, mpz was restricted to using at most 15 bits in each digit,
where a digit was a uint16_t.
With this patch, mpz can use all 16 bits in the uint16_t (improvement
to mpn_div was required). This gives small inprovements in speed and
RAM usage. It also yields savings in ROM code size because all of the
digit masking operations become no-ops.
Also, mpz can now use a uint32_t as the digit type, and hence use 32
bits per digit. This will give decent improvements in mpz speed on
64-bit machines.
Test for big integer division added.
Code-info size, block name, source name, n_state and n_exc_stack now use
variable length encoded uints. This saves 7-9 bytes per bytecode
function for most functions.
Damien George
Paul Sokolovsky