tccpp.c:
* #pragma comment(option,"-some-option")
to set commandline option from C code. May work only
for some options.
libtcc.c:
* option "-d1..9": sets a 'g_debug' global variable.
(for development)
tests2/Makefile:
* new make targets: tests2.37 / tests2.37+
run single test from tests2, optionally update .expect
* new variable GEN-ALWAYS to always generate certain .expects
* bitfields test
tccgen.c:
* bitfields: fix a bug and improve slightly more
* _Generic: ignore "type match twice"
