Avoid depending on CPython micro level versions at compile time. Compiling...

Avoid depending on CPython micro level versions at compile time. Compiling against 3.5.2 does not guarantee that we never get imported on 3.5.1.
Closes #1880.

Cython/Utility/Coroutine.c

@@ -1893,7 +1893,8 @@ _module._COROUTINE_TYPES = coro_types
             );
         } else {
             PyErr_Clear();
-#if PY_VERSION_HEX < 0x03040200
+// Always enable fallback: even if we compile against 3.4.2, we might be running on 3.4.1 at some point.
+//#if PY_VERSION_HEX < 0x03040200
             // Py3.4.1 used to have asyncio.tasks instead of asyncio.coroutines
             package = __Pyx_Import(PYIDENT("asyncio.tasks"), NULL, 0);
             if (unlikely(!package)) goto asyncio_done;
@@ -1914,15 +1915,15 @@ if hasattr(_module, 'iscoroutine'):
         old_types.add(_cython_generator_type)
 """)
             );
-#endif
+//#endif
 // Py < 0x03040200
         }
         Py_DECREF(package);
         if (unlikely(!patch_module)) goto ignore;
-#if PY_VERSION_HEX < 0x03040200
+//#if PY_VERSION_HEX < 0x03040200
 asyncio_done:
         PyErr_Clear();
-#endif
+//#endif
         asyncio_patched = 1;
 #ifdef __Pyx_Generator_USED
         // now patch inspect.isgenerator() by looking up the imported module in the patched asyncio module

Cython/Utility/Exceptions.c

@@ -12,14 +12,15 @@
 #if CYTHON_FAST_THREAD_STATE
 #define __Pyx_PyThreadState_declare  PyThreadState *$local_tstate_cname;
 #define __Pyx_PyErr_Occurred()  $local_tstate_cname->curexc_type
-#if PY_VERSION_HEX >= 0x03050000
+#if PY_VERSION_HEX >= 0x03060000
+  // Actually added in 3.5.2, but compiling against that does not guarantee that we get imported there.
   #define __Pyx_PyThreadState_assign  $local_tstate_cname = _PyThreadState_UncheckedGet();
 #elif PY_VERSION_HEX >= 0x03000000
-  #define __Pyx_PyThreadState_assign  $local_tstate_cname = PyThreadState_Get();
+  #define __Pyx_PyThreadState_assign  $local_tstate_cname = PyThreadState_GET();
 #elif PY_VERSION_HEX >= 0x02070000
   #define __Pyx_PyThreadState_assign  $local_tstate_cname = _PyThreadState_Current;
 #else
-  #define __Pyx_PyThreadState_assign  $local_tstate_cname = PyThreadState_Get();
+  #define __Pyx_PyThreadState_assign  $local_tstate_cname = PyThreadState_GET();
 #endif
 #else
 #define __Pyx_PyThreadState_declare

Cython/Utility/ModuleSetupCode.c

@@ -247,10 +247,11 @@
 
 #if !CYTHON_FAST_THREAD_STATE || PY_VERSION_HEX < 0x02070000
   #define __Pyx_PyThreadState_Current PyThreadState_GET()
-#elif PY_VERSION_HEX >= 0x03050200
+#if PY_VERSION_HEX >= 0x03060000
+//#elif PY_VERSION_HEX >= 0x03050200
   #define __Pyx_PyThreadState_Current _PyThreadState_UncheckedGet()
 #elif PY_VERSION_HEX >= 0x03000000
-  #define __Pyx_PyThreadState_Current PyThreadState_Get()
+  #define __Pyx_PyThreadState_Current PyThreadState_GET()
 #else
   #define __Pyx_PyThreadState_Current _PyThreadState_Current
 #endif