python-cffi: use gcc-style barrier on Windows.

The existing logic excluded this on i386, x86_64, and WIN32, presumably
because they assumed WIN32 was i386 or x86_64.  This patch enables
gcc-style __sync_synchronize(), if it compiles, on WIN32 if not i386 or
x86_64.

mingw-w64-python-cffi/PKGBUILD

@@ -7,7 +7,7 @@ provides=("${MINGW_PACKAGE_PREFIX}-python3-${_realname}")
 conflicts=("${MINGW_PACKAGE_PREFIX}-python3-${_realname}")
 replaces=("${MINGW_PACKAGE_PREFIX}-python3-${_realname}")
 pkgver=1.14.5
-pkgrel=1
+pkgrel=2
 pkgdesc="Foreign Function Interface for Python calling C code (mingw-w64)"
 url='https://cffi.readthedocs.io/'
 license=('MIT')
@@ -17,12 +17,16 @@ depends=("${MINGW_PACKAGE_PREFIX}-libffi"
          "${MINGW_PACKAGE_PREFIX}-python-pycparser")
 makedepends=("${MINGW_PACKAGE_PREFIX}-python-setuptools")
 checkdepends=("${MINGW_PACKAGE_PREFIX}-python-pytest-runner")
-source=("https://foss.heptapod.net/pypy/cffi/-/archive/v${pkgver}/${_realname}-v${pkgver}.tar.bz2")
-sha256sums=('d99690c6fe2efa7b60d0abb3ea6f30fd544d15ee01909328ea2d1991939d4162')
+source=("https://foss.heptapod.net/pypy/cffi/-/archive/v${pkgver}/${_realname}-v${pkgver}.tar.bz2"
+        "mingw-non-x86.patch")
+sha256sums=('d99690c6fe2efa7b60d0abb3ea6f30fd544d15ee01909328ea2d1991939d4162'
+            'c8a8ea2d65932ea0b62eae56dbc8afd6baacaadc7cb284ca0e4edf7ed1460c52')
 
 prepare() {
   cd "${srcdir}"
   cp -r "${_realname}-v${pkgver}" "python-build-${CARCH}"
+  cd "python-build-${CARCH}"
+  patch -Np1 -i "${srcdir}"/mingw-non-x86.patch
 }
 
 build() {

mingw-w64-python-cffi/mingw-non-x86.patch

@@ -0,0 +1,11 @@
+--- cffi-v1.14.4/setup.py.orig	2021-01-22 18:37:13.453727900 -0800
++++ cffi-v1.14.4/setup.py	2021-01-22 18:38:01.125798300 -0800
+@@ -90,7 +89,7 @@
+             _safe_to_ignore()
+ 
+ def ask_supports_sync_synchronize():
+-    if sys.platform == 'win32' or no_compiler_found:
++    if no_compiler_found:
+         return
+     config = get_config()
+     ok = config.try_link('int main(void) { __sync_synchronize(); return 0; }')