bpo-34649: Add missing NULL checks to _encoded_const() (GH-9225)

Alexey Izbyshev · berkerpeksag · commit 6f82bffd2df6 · 2018-09-13T00:05:20.000+03:00
Reported by Svace static analyzer.
diff --git a/Modules/_json.c b/Modules/_json.c
@@ -1374,23 +1374,23 @@ _encoded_const(PyObject *obj)
         if (s_null == NULL) {
             s_null = PyUnicode_InternFromString("null");
         }
-        Py_INCREF(s_null);
+        Py_XINCREF(s_null);
         return s_null;
     }
     else if (obj == Py_True) {
         static PyObject *s_true = NULL;
         if (s_true == NULL) {
             s_true = PyUnicode_InternFromString("true");
         }
-        Py_INCREF(s_true);
+        Py_XINCREF(s_true);
         return s_true;
     }
     else if (obj == Py_False) {
         static PyObject *s_false = NULL;
         if (s_false == NULL) {
             s_false = PyUnicode_InternFromString("false");
         }
-        Py_INCREF(s_false);
+        Py_XINCREF(s_false);
         return s_false;
     }
     else {

Original file line number	Diff line number	Diff line change
`@@ -1374,23 +1374,23 @@ _encoded_const(PyObject *obj)`
`1374`	`1374`	`if (s_null == NULL) {`
`1375`	`1375`	`s_null = PyUnicode_InternFromString("null");`
`1376`	`1376`	`}`
`1377`		`- Py_INCREF(s_null);`
	`1377`	`+ Py_XINCREF(s_null);`
`1378`	`1378`	`return s_null;`
`1379`	`1379`	`}`
`1380`	`1380`	`else if (obj == Py_True) {`
`1381`	`1381`	`static PyObject *s_true = NULL;`
`1382`	`1382`	`if (s_true == NULL) {`
`1383`	`1383`	`s_true = PyUnicode_InternFromString("true");`
`1384`	`1384`	`}`
`1385`		`- Py_INCREF(s_true);`
	`1385`	`+ Py_XINCREF(s_true);`
`1386`	`1386`	`return s_true;`
`1387`	`1387`	`}`
`1388`	`1388`	`else if (obj == Py_False) {`
`1389`	`1389`	`static PyObject *s_false = NULL;`
`1390`	`1390`	`if (s_false == NULL) {`
`1391`	`1391`	`s_false = PyUnicode_InternFromString("false");`
`1392`	`1392`	`}`
`1393`		`- Py_INCREF(s_false);`
	`1393`	`+ Py_XINCREF(s_false);`
`1394`	`1394`	`return s_false;`
`1395`	`1395`	`}`
`1396`	`1396`	`else {`