4 files changed, 25 insertions, 11 deletions
diff --git a/python/cache.cc b/python/cache.cc
index a1a865af..e527faba 100644
--- a/python/cache.cc
+++ b/python/cache.cc
@@ -286,7 +286,7 @@ static PyObject *PkgCacheGetFileList(PyObject *Self, void*) {
 
 static PyObject *PkgCacheGetIsMultiArch(PyObject *Self, void*) {
     pkgCache *Cache = GetCpp<pkgCache *>(Self);
-    PyBool_FromLong(Cache->MultiArchCache());
+    return PyBool_FromLong(Cache->MultiArchCache());
 } 
 
 static PyGetSetDef PkgCacheGetSet[] = {
diff --git a/python/progress.cc b/python/progress.cc
index a7fd7ae1..9e870875 100644
--- a/python/progress.cc
+++ b/python/progress.cc
@@ -28,6 +28,8 @@ inline bool setattr(PyObject *object, const char *attr, const char *fmt, T arg)
     if (!object)
         return false;
     PyObject *value = Py_BuildValue(fmt, arg);
+    if (value == NULL)
+       return false;
 
     int result = PyObject_SetAttrString(object, attr, value);
     Py_DECREF(value);
diff --git a/python/string.cc b/python/string.cc
index 7abe2d17..62aa34e7 100644
--- a/python/string.cc
+++ b/python/string.cc
@@ -64,17 +64,29 @@ MkInt(StrTimeRFC1123,TimeRFC1123, long long, "L");
 PyObject *StrSizeToStr(PyObject *Self,PyObject *Args)
 {
    PyObject *Obj;
+   double value;
+
    if (PyArg_ParseTuple(Args,"O",&Obj) == 0)
       return 0;
-   if (PyInt_Check(Obj))
-      return CppPyString(SizeToStr(PyInt_AsLong(Obj)));
+   // In Python 3, PyInt_Check is aliased to PyLong_Check and PyInt_AsLong is
+   // aliased to PyLong_AsLong.  Therefore we do the actual long checks first
+   // so that if it is a long in Python 3, the value will be converted to a
+   // double rather than a long.  This avoids OverflowError regressions in
+   // Python 3.  LP: #1030278
    if (PyLong_Check(Obj))
-      return CppPyString(SizeToStr(PyLong_AsDouble(Obj)));
-   if (PyFloat_Check(Obj))
-      return CppPyString(SizeToStr(PyFloat_AsDouble(Obj)));
-
-   PyErr_SetString(PyExc_TypeError,"Only understand integers and floats");
-   return 0;
+      value = PyLong_AsDouble(Obj);
+   else if (PyInt_Check(Obj))
+      value = PyInt_AsLong(Obj);
+   else if (PyFloat_Check(Obj))
+      value = PyFloat_AsDouble(Obj);
+   else {
+      PyErr_SetString(PyExc_TypeError,"Only understand integers and floats");
+      return 0;
+   }
+   // Check for OverflowErrors or other exceptions during conversion.
+   if (PyErr_Occurred())
+      return 0;
+   return CppPyString(SizeToStr(value));
 }
 
 PyObject *StrQuoteString(PyObject *Self,PyObject *Args)
diff --git a/python/tag.cc b/python/tag.cc
index 248d818d..6ae439f5 100644
--- a/python/tag.cc
+++ b/python/tag.cc
@@ -74,7 +74,7 @@ int TagFileClear(PyObject *self) {
     PyString_FromStringAndSize((v), (len))
 #define TagSecString_FromString(self, v) PyString_FromString(v)
 #else
-PyObject *TagSecString_FromStringAndSize(PyObject *self, const char *v,
+static PyObject *TagSecString_FromStringAndSize(PyObject *self, const char *v,
 	 				 Py_ssize_t len) {
    TagSecData *Self = (TagSecData *)self;
    if (Self->Bytes)
@@ -85,7 +85,7 @@ PyObject *TagSecString_FromStringAndSize(PyObject *self, const char *v,
       return PyUnicode_FromStringAndSize(v, len);
 }
 
-PyObject *TagSecString_FromString(PyObject *self, const char *v) {
+static PyObject *TagSecString_FromString(PyObject *self, const char *v) {
    TagSecData *Self = (TagSecData *)self;
    if (Self->Bytes)
       return PyBytes_FromString(v);