implement another try-finally corner case (the Py3 way only for now!):...

implement another try-finally corner case (the Py3 way only for now!): reraising a fresh exception in the finally clause

CHANGES.rst

@@ -83,6 +83,8 @@ Bugs fixed
 * The PEP 3155 ``__qualname__`` was incorrect for nested classes and
   inner classes/functions declared as ``global``.
 
+* Several corner cases in the try-finally statement were fixed.
+
 * The metaclass of a Python class was not inherited from its parent
   class(es).  It is now extracted from the list of base classes if not
   provided explicitly using the Py3 ``metaclass`` keyword argument.

Cython/Compiler/Nodes.py

@@ -5275,8 +5275,10 @@ class ReraiseStatNode(StatNode):
         vars = code.funcstate.exc_vars
         if vars:
             code.globalstate.use_utility_code(restore_exception_utility_code)
-            for varname in vars:
-                code.put_giveref(varname)
+            code.put_giveref(vars[0])
+            code.put_giveref(vars[1])
+            # fresh exceptions may not have a traceback yet (-> finally!)
+            code.put_xgiveref(vars[2])
             code.putln("__Pyx_ErrRestore(%s, %s, %s);" % tuple(vars))
             for varname in vars:
                 code.put("%s = 0; " % varname)
@@ -6506,7 +6508,10 @@ class TryFinallyStatNode(StatNode):
             finally_old_labels = code.all_new_labels()
 
             code.putln('{')
+            old_exc_vars = code.funcstate.exc_vars
+            code.funcstate.exc_vars = exc_vars[:3]
             fresh_finally_clause().generate_execution_code(code)
+            code.funcstate.exc_vars = old_exc_vars
             code.putln('}')
 
             if needs_success_cleanup:

tests/run/tryfinally.pyx

@@ -73,6 +73,31 @@ def except_finally_reraise():
         raise
 
 
+def except_finally_reraise_new():
+    """
+    >>> def py_check():
+    ...     try: raise ValueError
+    ...     except ValueError:
+    ...         try: raise TypeError
+    ...         finally:
+    ...             raise
+    >>> try: py_check()
+    ... except ValueError: assert not IS_PY3
+    ... except TypeError: assert IS_PY3
+    ... else: assert False
+    >>> try: except_finally_reraise_new()
+    ... except TypeError: pass  # currently only Py3 semantics implemented
+    ... else: assert False
+    """
+    try:
+        raise ValueError
+    except ValueError:
+        try:
+            raise TypeError
+        finally:
+            raise
+
+
 def finally_exception_check_return():
     """
     >>> if not IS_PY3: