diff --git a/pyearth/_basis.c b/pyearth/_basis.c
index 2b45571..f723939 100644
--- a/pyearth/_basis.c
+++ b/pyearth/_basis.c
@@ -2290,9 +2290,9 @@ typedef struct {
     PyObject_HEAD
     __pyx_coroutine_body_t body;
     PyObject *closure;
-    PyObject *exc_type;
-    PyObject *exc_value;
-    PyObject *exc_traceback;
+    PyObject *curexc_type;
+    PyObject *curexc_value;
+    PyObject *curexc_traceback;
     PyObject *gi_weakreflist;
     PyObject *classobj;
     PyObject *yieldfrom;
@@ -7772,9 +7772,9 @@ static __pyx_t_7pyearth_6_types_INDEX_t __pyx_f_7pyearth_6_basis_13BasisFunction
     } else {
       __pyx_t_1 = __pyx_t_8(__pyx_t_2);
       if (unlikely(!__pyx_t_1)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 177, __pyx_L1_error)
         }
         break;
@@ -26914,9 +26914,9 @@ static PyObject *__pyx_pf_7pyearth_6_basis_5Basis_21smooth_knots(struct __pyx_ob
       } else {
         __pyx_t_5 = __pyx_t_9(__pyx_t_6);
         if (unlikely(!__pyx_t_5)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 991, __pyx_L1_error)
           }
           break;
@@ -26988,9 +26988,9 @@ static PyObject *__pyx_pf_7pyearth_6_basis_5Basis_21smooth_knots(struct __pyx_ob
       } else {
         __pyx_t_5 = __pyx_t_9(__pyx_t_6);
         if (unlikely(!__pyx_t_5)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 993, __pyx_L1_error)
           }
           break;
@@ -27987,9 +27987,9 @@ static PyObject *__pyx_f_7pyearth_6_basis_5Basis_smooth(struct __pyx_obj_7pyeart
     } else {
       __pyx_t_3 = __pyx_t_8(__pyx_t_5);
       if (unlikely(!__pyx_t_3)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 1034, __pyx_L1_error)
         }
         break;
@@ -36293,17 +36293,17 @@ static CYTHON_INLINE void __Pyx_ErrFetchInState(PyThreadState *tstate, PyObject
     static CYTHON_INLINE int __Pyx_IterFinish(void) {
 #if CYTHON_FAST_THREAD_STATE
     PyThreadState *tstate = PyThreadState_GET();
-    PyObject* exc_type = tstate->curexc_type;
-    if (unlikely(exc_type)) {
-        if (likely(exc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration)) {
-            PyObject *exc_value, *exc_tb;
-            exc_value = tstate->curexc_value;
+    PyObject* curexc_type = tstate->curexc_type;
+    if (unlikely(curexc_type)) {
+        if (likely(curexc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration)) {
+            PyObject *curexc_value, *exc_tb;
+            curexc_value = tstate->curexc_value;
             exc_tb = tstate->curexc_traceback;
             tstate->curexc_type = 0;
             tstate->curexc_value = 0;
             tstate->curexc_traceback = 0;
-            Py_DECREF(exc_type);
-            Py_XDECREF(exc_value);
+            Py_DECREF(curexc_type);
+            Py_XDECREF(curexc_value);
             Py_XDECREF(exc_tb);
             return 0;
         } else {
@@ -37298,21 +37298,21 @@ static PyObject* __Pyx_PyInt_AddObjC(PyObject *op1, PyObject *op2, CYTHON_UNUSED
 /* SaveResetException */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -37357,12 +37357,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -38599,10 +38599,10 @@ static PyObject* __Pyx_PyFloat_DivideObjC(PyObject *op1, PyObject *op2, double f
 /* PyErrExceptionMatches */
                   #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -40016,12 +40016,12 @@ static void __Pyx_ReleaseBuffer(Py_buffer *view) {
                   #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSwap(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = *type;
-    tstate->exc_value = *value;
-    tstate->exc_traceback = *tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = *type;
+    tstate->curexc_value = *value;
+    tstate->curexc_traceback = *tb;
     *type = tmp_type;
     *value = tmp_value;
     *tb = tmp_tb;
@@ -40129,15 +40129,15 @@ static int __Pyx_PyGen_FetchStopIterationValue(PyObject **pvalue) {
 #endif
 static CYTHON_INLINE
 void __Pyx_Coroutine_ExceptionClear(__pyx_CoroutineObject *self) {
-    PyObject *exc_type = self->exc_type;
-    PyObject *exc_value = self->exc_value;
-    PyObject *exc_traceback = self->exc_traceback;
-    self->exc_type = NULL;
-    self->exc_value = NULL;
-    self->exc_traceback = NULL;
-    Py_XDECREF(exc_type);
-    Py_XDECREF(exc_value);
-    Py_XDECREF(exc_traceback);
+    PyObject *curexc_type = self->curexc_type;
+    PyObject *curexc_value = self->curexc_value;
+    PyObject *curexc_traceback = self->curexc_traceback;
+    self->curexc_type = NULL;
+    self->curexc_value = NULL;
+    self->curexc_traceback = NULL;
+    Py_XDECREF(curexc_type);
+    Py_XDECREF(curexc_value);
+    Py_XDECREF(curexc_traceback);
 }
 static CYTHON_INLINE
 int __Pyx_Coroutine_CheckRunning(__pyx_CoroutineObject *gen) {
@@ -40169,16 +40169,16 @@ PyObject *__Pyx_Coroutine_SendEx(__pyx_CoroutineObject *self, PyObject *value) {
     if (value) {
 #if CYTHON_COMPILING_IN_PYPY || CYTHON_COMPILING_IN_PYSTON
 #else
-        if (self->exc_traceback) {
-            PyTracebackObject *tb = (PyTracebackObject *) self->exc_traceback;
+        if (self->curexc_traceback) {
+            PyTracebackObject *tb = (PyTracebackObject *) self->curexc_traceback;
             PyFrameObject *f = tb->tb_frame;
             Py_XINCREF(__pyx_tstate->frame);
             assert(f->f_back == NULL);
             f->f_back = __pyx_tstate->frame;
         }
 #endif
-        __Pyx_ExceptionSwap(&self->exc_type, &self->exc_value,
-                            &self->exc_traceback);
+        __Pyx_ExceptionSwap(&self->curexc_type, &self->curexc_value,
+                            &self->curexc_traceback);
     } else {
         __Pyx_Coroutine_ExceptionClear(self);
     }
@@ -40186,12 +40186,12 @@ PyObject *__Pyx_Coroutine_SendEx(__pyx_CoroutineObject *self, PyObject *value) {
     retval = self->body((PyObject *) self, value);
     self->is_running = 0;
     if (retval) {
-        __Pyx_ExceptionSwap(&self->exc_type, &self->exc_value,
-                            &self->exc_traceback);
+        __Pyx_ExceptionSwap(&self->curexc_type, &self->curexc_value,
+                            &self->curexc_traceback);
 #if CYTHON_COMPILING_IN_PYPY || CYTHON_COMPILING_IN_PYSTON
 #else
-        if (self->exc_traceback) {
-            PyTracebackObject *tb = (PyTracebackObject *) self->exc_traceback;
+        if (self->curexc_traceback) {
+            PyTracebackObject *tb = (PyTracebackObject *) self->curexc_traceback;
             PyFrameObject *f = tb->tb_frame;
             Py_CLEAR(f->f_back);
         }
@@ -40411,9 +40411,9 @@ static int __Pyx_Coroutine_traverse(PyObject *self, visitproc visit, void *arg)
     Py_VISIT(gen->closure);
     Py_VISIT(gen->classobj);
     Py_VISIT(gen->yieldfrom);
-    Py_VISIT(gen->exc_type);
-    Py_VISIT(gen->exc_value);
-    Py_VISIT(gen->exc_traceback);
+    Py_VISIT(gen->curexc_type);
+    Py_VISIT(gen->curexc_value);
+    Py_VISIT(gen->curexc_traceback);
     return 0;
 }
 static int __Pyx_Coroutine_clear(PyObject *self) {
@@ -40421,9 +40421,9 @@ static int __Pyx_Coroutine_clear(PyObject *self) {
     Py_CLEAR(gen->closure);
     Py_CLEAR(gen->classobj);
     Py_CLEAR(gen->yieldfrom);
-    Py_CLEAR(gen->exc_type);
-    Py_CLEAR(gen->exc_value);
-    Py_CLEAR(gen->exc_traceback);
+    Py_CLEAR(gen->curexc_type);
+    Py_CLEAR(gen->curexc_value);
+    Py_CLEAR(gen->curexc_traceback);
     Py_CLEAR(gen->gi_name);
     Py_CLEAR(gen->gi_qualname);
     return 0;
@@ -40556,9 +40556,9 @@ static __pyx_CoroutineObject *__Pyx__Coroutine_New(
     gen->resume_label = 0;
     gen->classobj = NULL;
     gen->yieldfrom = NULL;
-    gen->exc_type = NULL;
-    gen->exc_value = NULL;
-    gen->exc_traceback = NULL;
+    gen->curexc_type = NULL;
+    gen->curexc_value = NULL;
+    gen->curexc_traceback = NULL;
     gen->gi_weakreflist = NULL;
     Py_XINCREF(qualname);
     gen->gi_qualname = qualname;
diff --git a/pyearth/_forward.c b/pyearth/_forward.c
index 46af61f..d6c4eb3 100644
--- a/pyearth/_forward.c
+++ b/pyearth/_forward.c
@@ -5509,9 +5509,9 @@ static int __pyx_pf_7pyearth_8_forward_13ForwardPasser___init__(struct __pyx_obj
     } else {
       __pyx_t_11 = __pyx_t_16(__pyx_t_1);
       if (unlikely(!__pyx_t_11)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 127, __pyx_L1_error)
         }
         break;
@@ -8923,9 +8923,9 @@ static PyObject *__pyx_f_7pyearth_8_forward_13ForwardPasser_next_pair(struct __p
       } else {
         __pyx_t_1 = __pyx_t_14(__pyx_t_8);
         if (unlikely(!__pyx_t_1)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 342, __pyx_L1_error)
           }
           break;
@@ -19493,9 +19493,9 @@ static char *__pyx_memoryview_get_item_pointer(struct __pyx_memoryview_obj *__py
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_2);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(1, 389, __pyx_L1_error)
         }
         break;
@@ -23114,9 +23114,9 @@ static PyObject *_unellipsify(PyObject *__pyx_v_index, int __pyx_v_ndim) {
     } else {
       __pyx_t_7 = __pyx_t_6(__pyx_t_4);
       if (unlikely(!__pyx_t_7)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(1, 665, __pyx_L1_error)
         }
         break;
@@ -23725,9 +23725,9 @@ static struct __pyx_memoryview_obj *__pyx_memview_slice(struct __pyx_memoryview_
     } else {
       __pyx_t_9 = __pyx_t_8(__pyx_t_3);
       if (unlikely(!__pyx_t_9)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(1, 732, __pyx_L1_error)
         }
         break;
@@ -33796,17 +33796,17 @@ static PyObject* __Pyx_PyInt_SubtractCObj(PyObject *op1, PyObject *op2, CYTHON_U
         static CYTHON_INLINE int __Pyx_IterFinish(void) {
 #if CYTHON_FAST_THREAD_STATE
     PyThreadState *tstate = PyThreadState_GET();
-    PyObject* exc_type = tstate->curexc_type;
-    if (unlikely(exc_type)) {
-        if (likely(exc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration)) {
-            PyObject *exc_value, *exc_tb;
-            exc_value = tstate->curexc_value;
+    PyObject* curexc_type = tstate->curexc_type;
+    if (unlikely(curexc_type)) {
+        if (likely(curexc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration)) {
+            PyObject *curexc_value, *exc_tb;
+            curexc_value = tstate->curexc_value;
             exc_tb = tstate->curexc_traceback;
             tstate->curexc_type = 0;
             tstate->curexc_value = 0;
             tstate->curexc_traceback = 0;
-            Py_DECREF(exc_type);
-            Py_XDECREF(exc_value);
+            Py_DECREF(curexc_type);
+            Py_XDECREF(curexc_value);
             Py_XDECREF(exc_tb);
             return 0;
         } else {
@@ -33986,21 +33986,21 @@ static PyObject* __Pyx_PyInt_SubtractCObj(PyObject *op1, PyObject *op2, CYTHON_U
 /* SaveResetException */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -34010,10 +34010,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -34055,12 +34055,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -34261,12 +34261,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
           #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSwap(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = *type;
-    tstate->exc_value = *value;
-    tstate->exc_traceback = *tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = *type;
+    tstate->curexc_value = *value;
+    tstate->curexc_traceback = *tb;
     *type = tmp_type;
     *value = tmp_value;
     *tb = tmp_tb;
diff --git a/pyearth/_knot_search.c b/pyearth/_knot_search.c
index e2484ce..a22f9e2 100644
--- a/pyearth/_knot_search.c
+++ b/pyearth/_knot_search.c
@@ -27789,9 +27789,9 @@ static char *__pyx_memoryview_get_item_pointer(struct __pyx_memoryview_obj *__py
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_2);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 389, __pyx_L1_error)
         }
         break;
@@ -31520,9 +31520,9 @@ static PyObject *_unellipsify(PyObject *__pyx_v_index, int __pyx_v_ndim) {
     } else {
       __pyx_t_7 = __pyx_t_6(__pyx_t_4);
       if (unlikely(!__pyx_t_7)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 665, __pyx_L1_error)
         }
         break;
@@ -32137,9 +32137,9 @@ static struct __pyx_memoryview_obj *__pyx_memview_slice(struct __pyx_memoryview_
     } else {
       __pyx_t_9 = __pyx_t_8(__pyx_t_3);
       if (unlikely(!__pyx_t_9)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 732, __pyx_L1_error)
         }
         break;
@@ -43044,21 +43044,21 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_CallNoArg(PyObject *func) {
 /* SaveResetException */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -43068,10 +43068,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -43113,12 +43113,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -43319,12 +43319,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
           #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSwap(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = *type;
-    tstate->exc_value = *value;
-    tstate->exc_traceback = *tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = *type;
+    tstate->curexc_value = *value;
+    tstate->curexc_traceback = *tb;
     *type = tmp_type;
     *value = tmp_value;
     *tb = tmp_tb;
diff --git a/pyearth/_pruning.c b/pyearth/_pruning.c
index 68360c8..cbb7151 100644
--- a/pyearth/_pruning.c
+++ b/pyearth/_pruning.c
@@ -3272,9 +3272,9 @@ static int __pyx_pf_7pyearth_8_pruning_13PruningPasser___init__(struct __pyx_obj
     } else {
       __pyx_t_1 = __pyx_t_10(__pyx_t_4);
       if (unlikely(!__pyx_t_1)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 44, __pyx_L1_error)
         }
         break;
@@ -6041,9 +6041,9 @@ static PyObject *__pyx_f_7pyearth_8_pruning_13PruningPasser_run(struct __pyx_obj
         } else {
           __pyx_t_19 = __pyx_t_27(__pyx_t_2);
           if (unlikely(!__pyx_t_19)) {
-            PyObject* exc_type = PyErr_Occurred();
-            if (exc_type) {
-              if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+            PyObject* curexc_type = PyErr_Occurred();
+            if (curexc_type) {
+              if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
               else __PYX_ERR(0, 171, __pyx_L1_error)
             }
             break;
@@ -6090,9 +6090,9 @@ static PyObject *__pyx_f_7pyearth_8_pruning_13PruningPasser_run(struct __pyx_obj
         {
           __pyx_t_19 = __pyx_t_27(__pyx_t_2);
           if (unlikely(!__pyx_t_19)) {
-            PyObject* exc_type = PyErr_Occurred();
-            if (exc_type) {
-              if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+            PyObject* curexc_type = PyErr_Occurred();
+            if (curexc_type) {
+              if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
               else __PYX_ERR(0, 173, __pyx_L1_error)
             }
             break;
@@ -6575,9 +6575,9 @@ static PyObject *__pyx_f_7pyearth_8_pruning_13PruningPasser_run(struct __pyx_obj
     } else {
       __pyx_t_19 = __pyx_t_27(__pyx_t_10);
       if (unlikely(!__pyx_t_19)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 204, __pyx_L1_error)
         }
         break;
@@ -12832,17 +12832,17 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_CallNoArg(PyObject *func) {
       static CYTHON_INLINE int __Pyx_IterFinish(void) {
 #if CYTHON_FAST_THREAD_STATE
     PyThreadState *tstate = PyThreadState_GET();
-    PyObject* exc_type = tstate->curexc_type;
-    if (unlikely(exc_type)) {
-        if (likely(exc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration)) {
-            PyObject *exc_value, *exc_tb;
-            exc_value = tstate->curexc_value;
+    PyObject* curexc_type = tstate->curexc_type;
+    if (unlikely(curexc_type)) {
+        if (likely(curexc_type == PyExc_StopIteration) || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration)) {
+            PyObject *curexc_value, *exc_tb;
+            curexc_value = tstate->curexc_value;
             exc_tb = tstate->curexc_traceback;
             tstate->curexc_type = 0;
             tstate->curexc_value = 0;
             tstate->curexc_traceback = 0;
-            Py_DECREF(exc_type);
-            Py_XDECREF(exc_value);
+            Py_DECREF(curexc_type);
+            Py_XDECREF(curexc_value);
             Py_XDECREF(exc_tb);
             return 0;
         } else {
@@ -13624,21 +13624,21 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 /* SaveResetException */
           #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -13648,10 +13648,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
           #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -13693,12 +13693,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
diff --git a/pyearth/_qr.c b/pyearth/_qr.c
index b8ce3bd..ede3fe9 100644
--- a/pyearth/_qr.c
+++ b/pyearth/_qr.c
@@ -15056,9 +15056,9 @@ static char *__pyx_memoryview_get_item_pointer(struct __pyx_memoryview_obj *__py
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_2);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 389, __pyx_L1_error)
         }
         break;
@@ -18677,9 +18677,9 @@ static PyObject *_unellipsify(PyObject *__pyx_v_index, int __pyx_v_ndim) {
     } else {
       __pyx_t_7 = __pyx_t_6(__pyx_t_4);
       if (unlikely(!__pyx_t_7)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 665, __pyx_L1_error)
         }
         break;
@@ -19288,9 +19288,9 @@ static struct __pyx_memoryview_obj *__pyx_memview_slice(struct __pyx_memoryview_
     } else {
       __pyx_t_9 = __pyx_t_8(__pyx_t_3);
       if (unlikely(!__pyx_t_9)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(2, 732, __pyx_L1_error)
         }
         break;
@@ -28474,21 +28474,21 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 /* SaveResetException */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -28498,10 +28498,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
         #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -28543,12 +28543,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -28749,12 +28749,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
           #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSwap(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = *type;
-    tstate->exc_value = *value;
-    tstate->exc_traceback = *tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = *type;
+    tstate->curexc_value = *value;
+    tstate->curexc_traceback = *tb;
     *type = tmp_type;
     *value = tmp_value;
     *tb = tmp_tb;
diff --git a/pyearth/_record.c b/pyearth/_record.c
index ebbd2dd..acde8f4 100644
--- a/pyearth/_record.c
+++ b/pyearth/_record.c
@@ -5831,9 +5831,9 @@ static PyObject *__pyx_pf_7pyearth_7_record_17PruningPassRecord_16partial_str(st
     } else {
       __pyx_t_2 = __pyx_t_7(__pyx_t_6);
       if (unlikely(!__pyx_t_2)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 118, __pyx_L1_error)
         }
         break;
@@ -7304,9 +7304,9 @@ static PyObject *__pyx_pf_7pyearth_7_record_17ForwardPassRecord_12partial_str(st
     } else {
       __pyx_t_1 = __pyx_t_7(__pyx_t_6);
       if (unlikely(!__pyx_t_1)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 188, __pyx_L1_error)
         }
         break;
@@ -17371,21 +17371,21 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 /* SaveResetException */
       #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -17395,10 +17395,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
       #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -17440,12 +17440,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
diff --git a/pyearth/_types.c b/pyearth/_types.c
index ffa8a43..b6248fb 100644
--- a/pyearth/_types.c
+++ b/pyearth/_types.c
@@ -4621,21 +4621,21 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 /* SaveResetException */
   #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -4645,10 +4645,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
   #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -4690,12 +4690,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
diff --git a/pyearth/_util.c b/pyearth/_util.c
index 63f323a..9efe224 100644
--- a/pyearth/_util.c
+++ b/pyearth/_util.c
@@ -2991,9 +2991,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_3);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 63, __pyx_L1_error)
         }
         break;
@@ -3051,9 +3051,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_3);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 64, __pyx_L1_error)
         }
         break;
@@ -3109,9 +3109,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
       } else {
         __pyx_t_9 = __pyx_t_8(__pyx_t_7);
         if (unlikely(!__pyx_t_9)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 65, __pyx_L1_error)
           }
           break;
@@ -3239,9 +3239,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
     } else {
       __pyx_t_2 = __pyx_t_4(__pyx_t_3);
       if (unlikely(!__pyx_t_2)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 69, __pyx_L1_error)
         }
         break;
@@ -3407,9 +3407,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
       } else {
         __pyx_t_7 = __pyx_t_4(__pyx_t_2);
         if (unlikely(!__pyx_t_7)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 77, __pyx_L1_error)
           }
           break;
@@ -3587,9 +3587,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
     } else {
       __pyx_t_5 = __pyx_t_4(__pyx_t_2);
       if (unlikely(!__pyx_t_5)) {
-        PyObject* exc_type = PyErr_Occurred();
-        if (exc_type) {
-          if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+        PyObject* curexc_type = PyErr_Occurred();
+        if (curexc_type) {
+          if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
           else __PYX_ERR(0, 84, __pyx_L1_error)
         }
         break;
@@ -3678,9 +3678,9 @@ static PyObject *__pyx_f_7pyearth_5_util_ascii_table(PyObject *__pyx_v_header, P
       } else {
         __pyx_t_12 = __pyx_t_8(__pyx_t_7);
         if (unlikely(!__pyx_t_12)) {
-          PyObject* exc_type = PyErr_Occurred();
-          if (exc_type) {
-            if (likely(exc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(exc_type, PyExc_StopIteration))) PyErr_Clear();
+          PyObject* curexc_type = PyErr_Occurred();
+          if (curexc_type) {
+            if (likely(curexc_type == PyExc_StopIteration || PyErr_GivenExceptionMatches(curexc_type, PyExc_StopIteration))) PyErr_Clear();
             else __PYX_ERR(0, 87, __pyx_L1_error)
           }
           break;
@@ -8068,21 +8068,21 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 /* SaveResetException */
     #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE void __Pyx__ExceptionSave(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb) {
-    *type = tstate->exc_type;
-    *value = tstate->exc_value;
-    *tb = tstate->exc_traceback;
+    *type = tstate->curexc_type;
+    *value = tstate->curexc_value;
+    *tb = tstate->curexc_traceback;
     Py_XINCREF(*type);
     Py_XINCREF(*value);
     Py_XINCREF(*tb);
 }
 static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) {
     PyObject *tmp_type, *tmp_value, *tmp_tb;
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = type;
-    tstate->exc_value = value;
-    tstate->exc_traceback = tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = type;
+    tstate->curexc_value = value;
+    tstate->curexc_traceback = tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);
@@ -8092,10 +8092,10 @@ static CYTHON_INLINE void __Pyx__ExceptionReset(PyThreadState *tstate, PyObject
 /* PyErrExceptionMatches */
     #if CYTHON_FAST_THREAD_STATE
 static CYTHON_INLINE int __Pyx_PyErr_ExceptionMatchesInState(PyThreadState* tstate, PyObject* err) {
-    PyObject *exc_type = tstate->curexc_type;
-    if (exc_type == err) return 1;
-    if (unlikely(!exc_type)) return 0;
-    return PyErr_GivenExceptionMatches(exc_type, err);
+    PyObject *curexc_type = tstate->curexc_type;
+    if (curexc_type == err) return 1;
+    if (unlikely(!curexc_type)) return 0;
+    return PyErr_GivenExceptionMatches(curexc_type, err);
 }
 #endif
 
@@ -8137,12 +8137,12 @@ static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb)
     *value = local_value;
     *tb = local_tb;
 #if CYTHON_FAST_THREAD_STATE
-    tmp_type = tstate->exc_type;
-    tmp_value = tstate->exc_value;
-    tmp_tb = tstate->exc_traceback;
-    tstate->exc_type = local_type;
-    tstate->exc_value = local_value;
-    tstate->exc_traceback = local_tb;
+    tmp_type = tstate->curexc_type;
+    tmp_value = tstate->curexc_value;
+    tmp_tb = tstate->curexc_traceback;
+    tstate->curexc_type = local_type;
+    tstate->curexc_value = local_value;
+    tstate->curexc_traceback = local_tb;
     Py_XDECREF(tmp_type);
     Py_XDECREF(tmp_value);
     Py_XDECREF(tmp_tb);