[pypy-commit] cffi default: Issue #350: more mess on Windows with Py_LIMITED_API

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r3054:164e526a5515
Date: 2018-01-08 11:03 +0100
http://bitbucket.org/cffi/cffi/changeset/164e526a5515/

Log:	Issue #350: more mess on Windows with Py_LIMITED_API

diff --git a/cffi/_cffi_include.h b/cffi/_cffi_include.h
--- a/cffi/_cffi_include.h
+++ b/cffi/_cffi_include.h
@@ -7,11 +7,38 @@
    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.
+
+   Issue #350: more mess: on Windows, 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.
 */
 #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 _WIN32
+#    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 _DEBUG is not set"
+#      endif
+#      if defined(Py_TRACE_REFS)
+#        error "pyconfig.h unexpectedly defines Py_TRACE_REFS"
+#      endif
+#      if defined(Py_REF_DEBUG)
+#        error "pyconfig.h unexpectedly defines Py_REF_DEBUG"
+#      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