tccgen.c:
  doubles need to be aligned, on ARM.  The section_reserve()
  in init_putv does not do that.
-D ONE_SOURCE: is now the default and not longer needed. Also,
  tcc.h now sets the default native target.  These both make
  compiling tcc simple as "gcc tcc.c -o tcc -ldl" again.
arm-asm.c:
  enable pseudo asm also for inline asm
tests/tests2/Makefile:
  disable bitfield tests except on windows and x86_64
  and don't generate-always
tcc.c:
  fix a loop with -dt on errors
configure:
  print compiler version (as recognized)
tccpp.c:
  actually define symbols for tcc -dt
  clear static variables (needed for -dt or libtcc usage)
96_nodata_wanted.c:
  use __label__ instead of asm
lib/files:
  use native symbols (__i386__ etc.) instead of TCC_TARGET_...

This works only when tcc.exe is compiled using MSC.  MinGW does
something in the startup code that defeats it.

To make this the default, enable this line in libtcc.c:tcc_new:

    #if defined(TCC_TARGET_PE) && 0
        s->leading_underscore = 1;

and then recompile tcc and also libtcc1.a

This is to make cross build of libtcc1.a easier.

Needed to handle signal() etc. with msvcrt

This enables native unwind semantics with longjmp on
win64 by putting an entry into the .pdata section for
each compiled fuction.

Also, the function now use a fixed stack and store arguments
into X(%rsp) rather than using push.