Fix building _ctypes extension on windows

Author: timfel

graalpython/com.oracle.graal.python.cext/CMakeLists.txt

@@ -399,10 +399,15 @@ target_link_libraries("_ctypes" PRIVATE ${FFI_LIBRARY})
 target_include_directories("_ctypes" BEFORE PRIVATE ${FFI_INCLUDE})
 
 if(WIN32)
+    target_compile_options("_ctypes" PRIVATE
+        /wd4201 # ffi.h(332): warning C4201: nonstandard extension used: nameless struct/union
+        /wd4457 # _ctypes.c(4783): warning C4457: declaration of 'item' hides function parameter
+    )
     target_compile_definitions("_ctypes" PRIVATE
         MS_WIN32
         MS_WIN64
         _WIN64
+        FFI_STATIC_BUILD
     )
 else()
     target_compile_definitions("_ctypes" PRIVATE

mx.graalpython/suite.py

@@ -673,6 +673,7 @@
                             "TRUFFLE_NFI_H_INC": "<path:com.oracle.truffle.nfi.native>/include",
                             "GRAALPY_PARENT_DIR": "<suite_parent:graalpython>",
                             "GRAALPY_EXT": "<graalpy_ext>",
+                            "LIBFFI_DIST": "<output_root:truffle:LIBFFI_DIST>/<os>-<arch>/<multitarget_libc_selection>/"
                         },
                         "results": [
                             "bin/<lib:python-native>",