C++ compiler cleanup: extern "C" a couple declarations, cast int to size_t

Python/sysmodule.c

@@ -700,6 +700,10 @@ a 11-tuple where the entries in the tuple are counts of:\n\
 10. Number of stack pops performed by call_function()"
 );
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #ifdef Py_TRACE_REFS
 /* Defined in objects.c because it uses static globals if that file */
 extern PyObject *_Py_GetObjects(PyObject *, PyObject *);
@@ -710,6 +714,10 @@ extern PyObject *_Py_GetObjects(PyObject *, PyObject *);
 extern PyObject *_Py_GetDXProfile(PyObject *,  PyObject *);
 #endif
 
+#ifdef __cplusplus
+}
+#endif
+
 static PyMethodDef sys_methods[] = {
 	/* Might as well keep this in alphabetic order */
 	{"callstats", (PyCFunction)PyEval_GetCallStats, METH_NOARGS,
@@ -1414,7 +1422,7 @@ mywrite(char *name, FILE *fp, const char *format, va_list va)
 			PyErr_Clear();
 			fputs(buffer, fp);
 		}
-		if (written < 0 || written >= sizeof(buffer)) {
+		if (written < 0 || (size_t)written >= sizeof(buffer)) {
 			const char *truncated = "... truncated";
 			if (PyFile_WriteString(truncated, file) != 0) {
 				PyErr_Clear();