diff -r bb67b810aac1 Lib/test/test_extcall.py
--- a/Lib/test/test_extcall.py	Mon Feb 23 07:56:13 2015 -0800
+++ b/Lib/test/test_extcall.py	Tue Feb 24 04:26:45 2015 +0000
@@ -92,7 +92,7 @@
     >>> g(*Nothing())
     Traceback (most recent call last):
       ...
-    TypeError: g() argument after * must be a sequence, not Nothing
+    TypeError: g() argument after * must be an iterable, not Nothing
 
     >>> class Nothing:
     ...     def __len__(self): return 5
@@ -101,7 +101,7 @@
     >>> g(*Nothing())
     Traceback (most recent call last):
       ...
-    TypeError: g() argument after * must be a sequence, not Nothing
+    TypeError: g() argument after * must be an iterable, not Nothing
 
     >>> class Nothing():
     ...     def __len__(self): return 5
@@ -127,6 +127,45 @@
     >>> g(*Nothing())
     0 (1, 2, 3) {}
 
+Check for issue #4806: Does a TypeError in a generator get propagated with the
+right error message? (Also check with other iterables.)
+
+    >>> def broken(): raise TypeError("myerror")
+    ...
+
+    >>> g(*(broken() for i in range(1)))
+    Traceback (most recent call last):
+      ...
+    TypeError: myerror
+
+    >>> class BrokenIterable1:
+    ...     def __iter__(self):
+    ...         raise TypeError('myerror')
+    ...
+    >>> g(*BrokenIterable1())
+    Traceback (most recent call last):
+      ...
+    TypeError: myerror
+
+    >>> class BrokenIterable2:
+    ...     def __iter__(self):
+    ...         yield 0
+    ...         raise TypeError('myerror')
+    ...
+    >>> g(*BrokenIterable2())
+    Traceback (most recent call last):
+      ...
+    TypeError: myerror
+
+    >>> class BrokenSequence:
+    ...     def __getitem__(self, idx):
+    ...         raise TypeError('myerror')
+    ...
+    >>> f(*BrokenSequence())
+    Traceback (most recent call last):
+      ...
+    TypeError: myerror
+
 Make sure that the function doesn't stomp the dictionary
 
     >>> d = {'a': 1, 'b': 2, 'c': 3}
@@ -166,17 +205,17 @@
     >>> h(*h)
     Traceback (most recent call last):
       ...
-    TypeError: h() argument after * must be a sequence, not function
+    TypeError: h() argument after * must be an iterable, not function
 
     >>> dir(*h)
     Traceback (most recent call last):
       ...
-    TypeError: dir() argument after * must be a sequence, not function
+    TypeError: dir() argument after * must be an iterable, not function
 
     >>> None(*h)
     Traceback (most recent call last):
       ...
-    TypeError: NoneType object argument after * must be a sequence, \
+    TypeError: NoneType object argument after * must be an iterable, \
 not function
 
     >>> h(**h)
diff -r bb67b810aac1 Python/ceval.c
--- a/Python/ceval.c	Mon Feb 23 07:56:13 2015 -0800
+++ b/Python/ceval.c	Tue Feb 24 04:26:45 2015 +0000
@@ -4550,16 +4550,18 @@
         stararg = EXT_POP(*pp_stack);
         if (!PyTuple_Check(stararg)) {
             PyObject *t = NULL;
+            if (Py_TYPE(stararg)->tp_iter == NULL &&
+                    !PySequence_Check(stararg)) {
+                PyErr_Format(PyExc_TypeError,
+                             "%.200s%.200s argument after * "
+                             "must be an iterable, not %.200s",
+                             PyEval_GetFuncName(func),
+                             PyEval_GetFuncDesc(func),
+                             stararg->ob_type->tp_name);
+                goto ext_call_fail;
+            }
             t = PySequence_Tuple(stararg);
             if (t == NULL) {
-                if (PyErr_ExceptionMatches(PyExc_TypeError)) {
-                    PyErr_Format(PyExc_TypeError,
-                                 "%.200s%.200s argument after * "
-                                 "must be a sequence, not %.200s",
-                                 PyEval_GetFuncName(func),
-                                 PyEval_GetFuncDesc(func),
-                                 stararg->ob_type->tp_name);
-                }
                 goto ext_call_fail;
             }
             Py_DECREF(stararg);