windows: look for different pyport.h content

Python 3.8 changed the content slightly. So we need to handle a
variant of the search string.

With this change, we get most of the way through a Python 3.8 static
build only to be stumped by missing symbols in libffi.

Author: indygreg

cpython-windows/build.py

@@ -890,7 +890,61 @@ def hack_project_files(
         )
 
 
-PYPORT_EXPORT_SEARCH = b"""
+PYPORT_EXPORT_SEARCH_NEW = b"""
+#if defined(__CYGWIN__)
+#       define HAVE_DECLSPEC_DLL
+#endif
+
+/* only get special linkage if built as shared or platform is Cygwin */
+#if defined(Py_ENABLE_SHARED) || defined(__CYGWIN__)
+#       if defined(HAVE_DECLSPEC_DLL)
+#               if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
+#                       define PyAPI_FUNC(RTYPE) __declspec(dllexport) RTYPE
+#                       define PyAPI_DATA(RTYPE) extern __declspec(dllexport) RTYPE
+        /* module init functions inside the core need no external linkage */
+        /* except for Cygwin to handle embedding */
+#                       if defined(__CYGWIN__)
+#                               define PyMODINIT_FUNC __declspec(dllexport) PyObject*
+#                       else /* __CYGWIN__ */
+#                               define PyMODINIT_FUNC PyObject*
+#                       endif /* __CYGWIN__ */
+#               else /* Py_BUILD_CORE */
+        /* Building an extension module, or an embedded situation */
+        /* public Python functions and data are imported */
+        /* Under Cygwin, auto-import functions to prevent compilation */
+        /* failures similar to those described at the bottom of 4.1: */
+        /* http://docs.python.org/extending/windows.html#a-cookbook-approach */
+#                       if !defined(__CYGWIN__)
+#                               define PyAPI_FUNC(RTYPE) __declspec(dllimport) RTYPE
+#                       endif /* !__CYGWIN__ */
+#                       define PyAPI_DATA(RTYPE) extern __declspec(dllimport) RTYPE
+        /* module init functions outside the core must be exported */
+#                       if defined(__cplusplus)
+#                               define PyMODINIT_FUNC extern "C" __declspec(dllexport) PyObject*
+#                       else /* __cplusplus */
+#                               define PyMODINIT_FUNC __declspec(dllexport) PyObject*
+#                       endif /* __cplusplus */
+#               endif /* Py_BUILD_CORE */
+#       endif /* HAVE_DECLSPEC_DLL */
+#endif /* Py_ENABLE_SHARED */
+
+/* If no external linkage macros defined by now, create defaults */
+#ifndef PyAPI_FUNC
+#       define PyAPI_FUNC(RTYPE) RTYPE
+#endif
+#ifndef PyAPI_DATA
+#       define PyAPI_DATA(RTYPE) extern RTYPE
+#endif
+#ifndef PyMODINIT_FUNC
+#       if defined(__cplusplus)
+#               define PyMODINIT_FUNC extern "C" PyObject*
+#       else /* __cplusplus */
+#               define PyMODINIT_FUNC PyObject*
+#       endif /* __cplusplus */
+#endif
+"""
+
+PYPORT_EXPORT_SEARCH_OLD = b"""
 #if defined(__CYGWIN__)
 #       define HAVE_DECLSPEC_DLL
 #endif
@@ -978,7 +1032,14 @@ def hack_source_files(source_path: pathlib.Path, static: bool):
     # dynamically linked. This is a useful property to have.
     if static:
         pyport_h = source_path / "Include" / "pyport.h"
-        static_replace_in_file(pyport_h, PYPORT_EXPORT_SEARCH, PYPORT_EXPORT_REPLACE)
+        try:
+            static_replace_in_file(
+                pyport_h, PYPORT_EXPORT_SEARCH_NEW, PYPORT_EXPORT_REPLACE
+            )
+        except NoSearchStringError:
+            static_replace_in_file(
+                pyport_h, PYPORT_EXPORT_SEARCH_OLD, PYPORT_EXPORT_REPLACE
+            )
 
     # Modules/_winapi.c and Modules/overlapped.c both define an
     # ``OverlappedType`` symbol. We rename one to make the symbol conflict