merge 0.19.x branch into master

Cython/Utility/Exceptions.c

@@ -135,7 +135,7 @@ raise_error:
 #else /* Python 3+ */
 
 static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject *cause) {
-    PyObject *owned_type = NULL, *owned_value = NULL, *owned_tb = NULL;
+    PyObject* owned_instance = NULL;
     if (tb == Py_None) {
         tb = 0;
     } else if (tb && !PyTraceBack_Check(tb)) {
@@ -143,9 +143,11 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
             "raise: arg 3 must be a traceback or None");
         goto bad;
     }
+    if (value == Py_None)
+        value = 0;
 
     if (PyExceptionInstance_Check(type)) {
-        if (value && value != Py_None) {
+        if (value) {
             PyErr_SetString(PyExc_TypeError,
                 "instance exception may not have a separate value");
             goto bad;
@@ -153,18 +155,45 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
         value = type;
         type = (PyObject*) Py_TYPE(value);
     } else if (PyExceptionClass_Check(type)) {
-        // instantiate the type now (we don't know when and how it will be caught)
-        PyErr_NormalizeException(&type, &value, &owned_tb);
-        if (!tb && owned_tb)
-            tb = owned_tb;
-        owned_type = type;
-        owned_value = value;
-        if (!PyExceptionInstance_Check(value)) {
-            PyErr_Format(PyExc_TypeError,
-                         "calling %R should have returned an instance of "
-                         "BaseException, not %R",
-                         type, Py_TYPE(value));
-            goto bad;
+        // make sure value is an exception instance of type
+        PyObject *instance_class = NULL;
+        if (value && PyExceptionInstance_Check(value)) {
+            instance_class = (PyObject*) Py_TYPE(value);
+            if (instance_class != type) {
+                if (PyObject_IsSubclass(instance_class, type)) {
+                    // believe the instance
+                    type = instance_class;
+                } else {
+                    instance_class = NULL;
+                }
+            }
+        }
+        if (!instance_class) {
+            // instantiate the type now (we don't know when and how it will be caught)
+            // assuming that 'value' is an argument to the type's constructor
+            // not using PyErr_NormalizeException() to avoid ref-counting problems
+            PyObject *args;
+            if (!value)
+                args = PyTuple_New(0);
+            else if (PyTuple_Check(value)) {
+                Py_INCREF(value);
+                args = value;
+            } else
+                args = PyTuple_Pack(1, value);
+            if (!args)
+                goto bad;
+            owned_instance = PyObject_Call(type, args, NULL);
+            Py_DECREF(args);
+            if (!owned_instance)
+                goto bad;
+            value = owned_instance;
+            if (!PyExceptionInstance_Check(value)) {
+                PyErr_Format(PyExc_TypeError,
+                             "calling %R should have returned an instance of "
+                             "BaseException, not %R",
+                             type, Py_TYPE(value));
+                goto bad;
+            }
         }
     } else {
         PyErr_SetString(PyExc_TypeError,
@@ -210,10 +239,7 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
     }
 
 bad:
-    Py_XDECREF(owned_type);
-    Py_XDECREF(owned_value);
-    Py_XDECREF(owned_tb);
-
+    Py_XDECREF(owned_instance);
     return;
 }
 #endif

tests/run/raise_memory_error_T650.pyx

@@ -2,6 +2,7 @@
 
 cimport cython
 
+
 @cython.test_assert_path_exists(
     '//RaiseStatNode',
     '//RaiseStatNode[@builtin_exc_name = "MemoryError"]')
@@ -13,6 +14,7 @@ def raise_me_type():
     """
     raise MemoryError
 
+
 @cython.test_assert_path_exists(
     '//RaiseStatNode',
     '//RaiseStatNode[@builtin_exc_name = "MemoryError"]')
@@ -24,6 +26,7 @@ def raise_me_instance():
     """
     raise MemoryError()
 
+
 def raise_me_instance_value():
     """
     >>> raise_me_instance_value()
@@ -32,3 +35,13 @@ def raise_me_instance_value():
     MemoryError: oom
     """
     raise MemoryError("oom")
+
+
+def raise_me_instance_value_separate():
+    """
+    >>> raise_me_instance_value_separate()
+    Traceback (most recent call last):
+        ...
+    MemoryError: oom
+    """
+    raise MemoryError, "oom"