Add utility for unbound locals exception and use it inside CCodeWriter.put_error_if_unbound

Cython/Compiler/Code.py

@@ -1420,16 +1420,17 @@ class CCodeWriter(object):
         return self.putln("if (%s < 0) %s" % (value, self.error_goto(pos)))
 
     def put_error_if_unbound(self, pos, entry):
-        self.put('if (unlikely(!%s)) { PyErr_SetString(' % entry.cname)
+        import ExprNodes
         if entry.from_closure:
-            self.put('PyExc_NameError, "')
-            self.put("free variable '%s' referenced before assignment in enclosing scope" %
-                     entry.name)
+            func = '__Pyx_RaiseClosureNameError'
+            self.globalstate.use_utility_code(
+                ExprNodes.raise_closure_name_error_utility_code)
         else:
-            self.put('PyExc_UnboundLocalError, "')
-            self.put("local variable '%s' referenced before assignment" %
-                     entry.name)
-        self.putln('"); %s }' % self.error_goto(pos))
+            func = '__Pyx_RaiseUnboundLocalError'
+            self.globalstate.use_utility_code(
+                ExprNodes.raise_unbound_local_error_utility_code)
+        self.put('if (unlikely(!%s)) { %s("%s"); %s }' % (
+            entry.cname, func, entry.name, self.error_goto(pos)))
 
     def set_error_info(self, pos):
         self.funcstate.should_declare_error_indicator = True

Cython/Compiler/ExprNodes.py

@@ -8280,6 +8280,26 @@ static CYTHON_INLINE void __Pyx_RaiseNoneNotIterableError(void) {
 }
 ''')
 
+raise_unbound_local_error_utility_code = UtilityCode(
+proto = """
+static CYTHON_INLINE void __Pyx_RaiseUnboundLocalError(const char *varname);
+""",
+impl = """
+static CYTHON_INLINE void __Pyx_RaiseUnboundLocalError(const char *varname) {
+    PyErr_Format(PyExc_UnboundLocalError, "local variable '%s' referenced before assignment", varname);
+}
+""")
+
+raise_closure_name_error_utility_code = UtilityCode(
+proto = """
+static CYTHON_INLINE void __Pyx_RaiseClosureNameError(const char *varname);
+""",
+impl = """
+static CYTHON_INLINE void __Pyx_RaiseClosureNameError(const char *varname) {
+    PyErr_Format(PyExc_NameError, "free variable '%s' referenced before assignment in enclosing scope", varname);
+}
+""")
+
 #------------------------------------------------------------------------------------
 
 getitem_dict_utility_code = UtilityCode(