clean up string comparison optimisation from github #1571

Cython/Utility/StringTools.c

@@ -39,8 +39,8 @@ static int __Pyx_InitStrings(__Pyx_StringTabEntry *t) {
         #endif
         if (!*t->p)
             return -1;
-        hash = PyObject_Hash(*t->p);
-        if (hash == -1)
+        // initialise cached hash value
+        if (PyObject_Hash(*t->p) == -1)
             PyErr_Clear();
         ++t;
     }
@@ -189,20 +189,20 @@ static CYTHON_INLINE int __Pyx_PyUnicode_Equals(PyObject* s1, PyObject* s2, int
         if (length != __Pyx_PyUnicode_GET_LENGTH(s2)) {
             goto return_ne;
         }
-#if CYTHON_COMPILING_IN_CPYTHON
-#if CYTHON_PEP393_ENABLED
-        if (((PyASCIIObject*)s1)->hash != ((PyASCIIObject*)s2)->hash
-            && ((PyASCIIObject*)s1)->hash != -1 && ((PyASCIIObject*)s2)->hash != -1)
-        {
-            goto return_ne;
-        }
-#else
-        if (((PyUnicodeObject*)s1)->hash != ((PyUnicodeObject*)s2)->hash
-            && ((PyUnicodeObject*)s1)->hash != -1 && ((PyUnicodeObject*)s2)->hash != -1)
+#if CYTHON_USE_UNICODE_INTERNALS
         {
-            goto return_ne;
+            Py_hash_t hash1, hash2;
+        #if CYTHON_PEP393_ENABLED
+            hash1 = ((PyASCIIObject*)s1)->hash;
+            hash2 = ((PyASCIIObject*)s2)->hash;
+        #else
+            hash1 = ((PyUnicodeObject*)s1)->hash;
+            hash2 = ((PyUnicodeObject*)s2)->hash;
+        #endif
+            if (hash1 != hash2 && hash1 != -1 && hash2 != -1) {
+                goto return_ne;
+            }
         }
-#endif
 #endif
         // len(s1) == len(s2) >= 1  (empty string is interned, and "s1 is not s2")
         kind = __Pyx_PyUnicode_KIND(s1);
@@ -276,14 +276,16 @@ static CYTHON_INLINE int __Pyx_PyBytes_Equals(PyObject* s1, PyObject* s2, int eq
         } else if (length == 1) {
             return (equals == Py_EQ);
         } else {
-#if CYTHON_COMPILING_IN_CPYTHON
-            if (((PyBytesObject*)s1)->ob_shash != ((PyBytesObject*)s2)->ob_shash
-                && ((PyBytesObject*)s1)->ob_shash != -1 && ((PyBytesObject*)s2)->ob_shash != -1)
-            {
+            int result;
+#if CYTHON_USE_UNICODE_INTERNALS
+            Py_hash_t hash1, hash2;
+            hash1 = ((PyBytesObject*)s1)->ob_shash;
+            hash2 = ((PyBytesObject*)s2)->ob_shash;
+            if (hash1 != hash2 && hash1 != -1 && hash2 != -1) {
                 return (equals == Py_NE);
             }
 #endif
-            int result = memcmp(ps1, ps2, (size_t)length);
+            result = memcmp(ps1, ps2, (size_t)length);
             return (equals == Py_EQ) ? (result == 0) : (result != 0);
         }
     } else if ((s1 == Py_None) & PyBytes_CheckExact(s2)) {