[pypy-commit] cffi ofekmeister/windows-support-py_limited_api-1534700268692: Redo 164e526a5515 and 14ce6985e1c3.

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: ofekmeister/windows-support-py_limited_api-1534700268692
Changeset: r3147:996c463c0b1d
Date: 2018-08-24 18:11 +0200
http://bitbucket.org/cffi/cffi/changeset/996c463c0b1d/

Log:	Redo 164e526a5515 and 14ce6985e1c3.

diff --git a/cffi/_cffi_include.h b/cffi/_cffi_include.h
--- a/cffi/_cffi_include.h
+++ b/cffi/_cffi_include.h
@@ -7,11 +7,44 @@
    we can learn about Py_DEBUG from pyconfig.h, but it is unclear if
    the same works for the other two macros.  Py_DEBUG implies them,
    but not the other way around.
+
+   The implementation is messy (issue #350): on Windows, with _MSC_VER,
+   we have to define Py_LIMITED_API even before including pyconfig.h.
+   In that case, we guess what pyconfig.h will do to the macros above,
+   and check our guess after the #include.
+
+   Note that on Windows, with CPython 3.x, you need virtualenv version
+   >= 16.0.0.  Older versions don't copy PYTHON3.DLL.  As a workaround
+   you can remove the definition of Py_LIMITED_API here.
+
+   See also 'py_limited_api' in cffi/setuptools_ext.py.
 */
 #if !defined(_CFFI_USE_EMBEDDING) && !defined(Py_LIMITED_API)
-#  include <pyconfig.h>
-#  if !defined(Py_DEBUG) && !defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG)
-#    define Py_LIMITED_API
+#  ifdef _MSC_VER
+#    if !defined(_DEBUG) && !defined(Py_DEBUG) && !defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG)
+#      define Py_LIMITED_API
+#    endif
+#    include <pyconfig.h>
+     /* sanity-check: Py_LIMITED_API will cause crashes if any of these
+        are also defined.  Normally, the Python file PC/pyconfig.h does not
+        cause any of these to be defined, with the exception that _DEBUG
+        causes Py_DEBUG.  Double-check that. */
+#    ifdef Py_LIMITED_API
+#      if defined(Py_DEBUG)
+#        error "pyconfig.h unexpectedly defines Py_DEBUG, but Py_LIMITED_API is set"
+#      endif
+#      if defined(Py_TRACE_REFS)
+#        error "pyconfig.h unexpectedly defines Py_TRACE_REFS, but Py_LIMITED_API is set"
+#      endif
+#      if defined(Py_REF_DEBUG)
+#        error "pyconfig.h unexpectedly defines Py_REF_DEBUG, but Py_LIMITED_API is set"
+#      endif
+#    endif
+#  else
+#    include <pyconfig.h>
+#    if !defined(Py_DEBUG) && !defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG)
+#      define Py_LIMITED_API
+#    endif
 #  endif
 #endif