bpo-35081: Internal headers require Py_BUILD_CORE (GH-10363)
* All internal header files now require Py_BUILD_CORE or
Py_BUILD_CORE_BUILTIN to be defined.
* _json.c is now compiled with Py_BUILD_CORE_BUILTIN to access
pycore_accu.h header.
* Add an example to Modules/Setup to show how to build _json
as a built-in module; it requires non trivial compiler options.
diff --git a/Modules/Setup b/Modules/Setup
index e2b5f86..e7b939d 100644
--- a/Modules/Setup
+++ b/Modules/Setup
@@ -180,6 +180,7 @@
#_bisect _bisectmodule.c # Bisection algorithms
#_heapq _heapqmodule.c # Heap queue algorithm
#_asyncio _asynciomodule.c # Fast asyncio Future
+#_json -I$(srcdir)/Include/internal -DPy_BUILD_CORE_BUILTIN _json.c # _json speedups
#unicodedata unicodedata.c # static Unicode character database