SF #1444030: Fix several potential defects found by Coverity.

(reviewed by Neal Norwitz)

Modules/arraymodule.c

@@ -1852,10 +1852,13 @@ array_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 					Py_DECREF(v);
 				}
 			} else if (initial != NULL && PyString_Check(initial)) {
-				PyObject *t_initial = PyTuple_Pack(1,
-								    initial);
-				PyObject *v =
-					array_fromstring((arrayobject *)a,
+				PyObject *t_initial, *v;
+				t_initial = PyTuple_Pack(1, initial);
+				if (t_initial == NULL) {
+					Py_DECREF(a);
+					return NULL;
+				}
+				v = array_fromstring((arrayobject *)a,
 							 t_initial);
 				Py_DECREF(t_initial);
 				if (v == NULL) {

Modules/cStringIO.c

@@ -544,6 +544,7 @@ newOobject(int  size) {
 	if (!self->buf) {
                   PyErr_SetString(PyExc_MemoryError,"out of memory");
                   self->buf_size = 0;
+                  Py_DECREF(self);
                   return NULL;
           }
 

Modules/zipimport.c

@@ -1167,6 +1167,8 @@ initzipimport(void)
 
 	mod = Py_InitModule4("zipimport", NULL, zipimport_doc,
 			     NULL, PYTHON_API_VERSION);
+	if (mod == NULL)
+		return;
 
 	ZipImportError = PyErr_NewException("zipimport.ZipImportError",
 					    PyExc_ImportError, NULL);

Objects/longobject.c

@@ -2809,6 +2809,8 @@ long_bitwise(PyLongObject *a,
 
 	if (a->ob_size < 0) {
 		a = (PyLongObject *) long_invert(a);
+		if (a == NULL)
+			return NULL;
 		maska = MASK;
 	}
 	else {
@@ -2817,6 +2819,10 @@ long_bitwise(PyLongObject *a,
 	}
 	if (b->ob_size < 0) {
 		b = (PyLongObject *) long_invert(b);
+		if (b == NULL) {
+			Py_DECREF(a);
+			return NULL;
+		}
 		maskb = MASK;
 	}
 	else {
@@ -2868,7 +2874,7 @@ long_bitwise(PyLongObject *a,
 		   : (maskb ? size_a : MIN(size_a, size_b)))
 		: MAX(size_a, size_b);
 	z = _PyLong_New(size_z);
-	if (a == NULL || b == NULL || z == NULL) {
+	if (z == NULL) {
 		Py_XDECREF(a);
 		Py_XDECREF(b);
 		Py_XDECREF(z);

Objects/stringobject.c

@@ -3276,7 +3276,7 @@ string_splitlines(PyStringObject *self, PyObject *args)
     return list;
 
  onError:
-    Py_DECREF(list);
+    Py_XDECREF(list);
     return NULL;
 }
 

Objects/unicodeobject.c

@@ -1876,16 +1876,16 @@ PyObject *PyUnicode_DecodeUnicodeEscape(const char *s,
             message = "malformed \\N character escape";
             if (ucnhash_CAPI == NULL) {
                 /* load the unicode data module */
-                PyObject *m, *v;
+                PyObject *m, *api;
                 m = PyImport_ImportModule("unicodedata");
                 if (m == NULL)
                     goto ucnhashError;
-                v = PyObject_GetAttrString(m, "ucnhash_CAPI");
+                api = PyObject_GetAttrString(m, "ucnhash_CAPI");
                 Py_DECREF(m);
-                if (v == NULL)
+                if (api == NULL)
                     goto ucnhashError;
-                ucnhash_CAPI = PyCObject_AsVoidPtr(v);
-                Py_DECREF(v);
+                ucnhash_CAPI = PyCObject_AsVoidPtr(api);
+                Py_DECREF(api);
                 if (ucnhash_CAPI == NULL)
                     goto ucnhashError;
             }
@@ -1945,6 +1945,7 @@ ucnhashError:
         PyExc_UnicodeError,
         "\\N escapes not supported (can't load unicodedata module)"
         );
+    Py_XDECREF(v);
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
     return NULL;
@@ -3962,7 +3963,7 @@ Py_ssize_t PyUnicode_Tailmatch(PyObject *str,
 	return -1;
     substr = PyUnicode_FromObject(substr);
     if (substr == NULL) {
-	Py_DECREF(substr);
+	Py_DECREF(str);
 	return -1;
     }
 
@@ -4429,7 +4430,7 @@ PyObject *PyUnicode_Splitlines(PyObject *string,
     return list;
 
  onError:
-    Py_DECREF(list);
+    Py_XDECREF(list);
     Py_DECREF(string);
     return NULL;
 }
@@ -6679,6 +6680,10 @@ formatlong(PyObject *val, int flags, int prec, int type)
 	if (!str)
 		return NULL;
 	result = _PyUnicode_New(len);
+	if (!result) {
+		Py_DECREF(str);
+		return NULL;
+	}
 	for (i = 0; i < len; i++)
 		result->str[i] = buf[i];
 	result->str[len] = 0;
@@ -6865,7 +6870,7 @@ PyObject *PyUnicode_Format(PyObject *format,
 		rescnt = fmtcnt + 100;
 		reslen += rescnt;
 		if (_PyUnicode_Resize(&result, reslen) < 0)
-		    return NULL;
+		    goto onError;
 		res = PyUnicode_AS_UNICODE(result) + reslen - rescnt;
 		--rescnt;
 	    }
@@ -7163,6 +7168,7 @@ PyObject *PyUnicode_Format(PyObject *format,
 		rescnt = width + fmtcnt + 100;
 		reslen += rescnt;
 		if (reslen < 0) {
+		    Py_XDECREF(temp);
 		    Py_DECREF(result);
 		    return PyErr_NoMemory();
 		}

Objects/weakrefobject.c

@@ -903,8 +903,15 @@ PyObject_ClearWeakRefs(PyObject *object)
             }
         }
         else {
-            PyObject *tuple = PyTuple_New(count * 2);
+            PyObject *tuple;
             Py_ssize_t i = 0;
+    
+            tuple = PyTuple_New(count * 2);
+            if (tuple == NULL) {
+                if (restore_error)
+                    PyErr_Fetch(&err_type, &err_value, &err_tb);
+                return;
+            }
 
             for (i = 0; i < count; ++i) {
                 PyWeakReference *next = current->wr_next;

Parser/firstsets.c

@@ -107,4 +107,6 @@ calcfirstset(grammar *g, dfa *d)
 		}
 		printf(" }\n");
 	}
+
+	PyMem_FREE(sym);
 }

Python/ast.c

@@ -1438,6 +1438,8 @@ ast_for_trailer(struct compiling *c, const node *n, expr_ty left_expr)
             }
             /* extract Index values and put them in a Tuple */
             elts = asdl_seq_new(asdl_seq_LEN(slices), c->c_arena);
+            if (!elts)
+                return NULL;
             for (j = 0; j < asdl_seq_LEN(slices); ++j) {
                 slc = (slice_ty)asdl_seq_GET(slices, j);
                 assert(slc->kind == Index_kind  && slc->v.Index.value);

Python/ceval.c

@@ -3477,8 +3477,11 @@ PyEval_CallObjectWithKeywords(PyObject *func, PyObject *arg, PyObject *kw)
 {
 	PyObject *result;
 
-	if (arg == NULL)
+	if (arg == NULL) {
 		arg = PyTuple_New(0);
+		if (arg == NULL)
+			return NULL;
+	}
 	else if (!PyTuple_Check(arg)) {
 		PyErr_SetString(PyExc_TypeError,
 				"argument list must be a tuple");

Python/traceback.c

@@ -185,8 +185,12 @@ tb_displayline(PyObject *f, char *filename, int lineno, char *name)
 	}
 	PyOS_snprintf(linebuf, sizeof(linebuf), FMT, filename, lineno, name);
 	err = PyFile_WriteString(linebuf, f);
-	if (xfp == NULL || err != 0)
+	if (xfp == NULL)
 		return err;
+	else if (err != 0) {
+		fclose(xfp);
+		return err;
+	}
 	for (i = 0; i < lineno; i++) {
 		char* pLastChar = &linebuf[sizeof(linebuf)-2];
 		do {