Support UCS-4 Tcl for UCS-4 Python builds. Fixes #719880.
diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index 303119f..c946f88 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -87,8 +87,12 @@
/* Unicode conversion assumes that Tcl_UniChar is two bytes.
We cannot test this directly, so we test UTF-8 size instead,
expecting that TCL_UTF_MAX is changed if Tcl ever supports
- either UTF-16 or UCS-4. */
-#if TCL_UTF_MAX != 3
+ either UTF-16 or UCS-4.
+ Redhat 8 sets TCL_UTF_MAX to 6, and uses wchar_t for
+ Tcl_Unichar. This is also ok as long as Python uses UCS-4,
+ as well.
+*/
+#if TCL_UTF_MAX != 3 && !(defined(Py_UNICODE_WIDE) && TCL_UTF_MAX==6)
#error "unsupported Tcl configuration"
#endif
@@ -899,7 +903,7 @@
int size = PyUnicode_GET_SIZE(value);
/* This #ifdef assumes that Tcl uses UCS-2.
See TCL_UTF_MAX test above. */
-#ifdef Py_UNICODE_WIDE
+#if defined(Py_UNICODE_WIDE) && TCL_UTF_MAX == 3
Tcl_UniChar *outbuf;
int i;
outbuf = (Tcl_UniChar*)ckalloc(size * sizeof(Tcl_UniChar));
@@ -1030,7 +1034,7 @@
if (value->typePtr == app->StringType) {
#ifdef Py_USING_UNICODE
-#ifdef Py_UNICODE_WIDE
+#if defined(Py_UNICODE_WIDE) && TCL_UTF_MAX==3
PyObject *result;
int size;
Tcl_UniChar *input;