Update to libffi 3.4.3

[zooba]

The issue described in #26204 should be resolved by this update.

It should be backported to all branches currently using 3.4.2.

[dpy013]

                cc

@ambv
and
@MaxwellDupre
Is it possible to submit a
pull request
to update libffi?

[zooba]

No, I need to do it, because we have to build it on our release infrastructure. Just haven't gotten to it because I've been sick.

[zooba]

Compilation error:

libtool: compile:  /cygdrive/c/Users/mick/programming/git/cpython-source-deps/msvcc.sh -DHAVE_CONFIG_H -I. -I.. -I. -I../include -Iinclude -I../src -DFFI_BUILDING_DLL -I. -I../include -Iinclude -I../src -c ../src/x86/sysv_intel.S  -DDLL_EXPORT -DPIC -o src/x86/.libs/sysv_intel.obj
sysv_intel.S
 Assembling: src/x86/.libs/sysv_intel.asm
src/x86/.libs/sysv_intel.asm(1807) : error A2008:syntax error : *
src/x86/.libs/sysv_intel.asm(1808) : error A2008:syntax error : *
make[3]: *** [Makefile:1279: src/x86/sysv_intel.lo] Error 1

[zooba]

Seems to be these lines:

https://github.com/python/cpython-source-deps/blob/ba2ec1402a4039f86f39962c90dc10f23630e71b/src/x86/sysv_intel.S#L758-L759

/* #endif /* DARWIN || HIDDEN */ */
/* #endif /* __PIC__ */ */

The preprocessor is handling the double */ */ differently, I assume, and ending the comment at the first one rather than treating them as nested (which I believe is incorrect anyway?)

I can patch it out of our copy of the sources and build anyway, just checking what else might break before committing it.

@atgreen FYI