diff --git a/Include/cpython/longintrepr.h b/Include/cpython/longintrepr.h
index 66623780ca9..d841c043f37 100644
--- a/Include/cpython/longintrepr.h
+++ b/Include/cpython/longintrepr.h
@@ -119,7 +119,7 @@ PyAPI_FUNC(PyLongObject*) _PyLong_FromDigits(
 
 
 static inline int
-_PyLong_IsCompact(const PyLongObject* op) {
+_PyLong_IsCompact(PyLongObject* op) {
     assert(PyType_HasFeature(Py_TYPE(op), Py_TPFLAGS_LONG_SUBCLASS));
     return op->long_value.lv_tag < (2 << _PyLong_NON_SIZE_BITS);
 }
@@ -127,7 +127,7 @@ _PyLong_IsCompact(const PyLongObject* op) {
 #define PyUnstable_Long_IsCompact _PyLong_IsCompact
 
 static inline Py_ssize_t
-_PyLong_CompactValue(const PyLongObject *op)
+_PyLong_CompactValue(PyLongObject *op)
 {
     Py_ssize_t sign;
     assert(PyType_HasFeature(Py_TYPE(op), Py_TPFLAGS_LONG_SUBCLASS));
diff --git a/Include/internal/pycore_long.h b/Include/internal/pycore_long.h
index 8513695c22e..2bf6ff459dd 100644
--- a/Include/internal/pycore_long.h
+++ b/Include/internal/pycore_long.h
@@ -240,7 +240,7 @@ static inline int
 _PyLong_CompactSign(const PyLongObject *op)
 {
     assert(PyLong_Check(op));
-    assert(_PyLong_IsCompact(op));
+    assert(_PyLong_IsCompact((PyLongObject *)op));
     return 1 - (op->long_value.lv_tag & SIGN_MASK);
 }
 
@@ -248,7 +248,7 @@ static inline int
 _PyLong_NonCompactSign(const PyLongObject *op)
 {
     assert(PyLong_Check(op));
-    assert(!_PyLong_IsCompact(op));
+    assert(!_PyLong_IsCompact((PyLongObject *)op));
     return 1 - (op->long_value.lv_tag & SIGN_MASK);
 }
 
diff --git a/Objects/longobject.c b/Objects/longobject.c
index a3a59a20f0b..86afec9a414 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -6672,12 +6672,12 @@ _PyLong_FiniTypes(PyInterpreterState *interp)
 
 int
 PyUnstable_Long_IsCompact(const PyLongObject* op) {
-    return _PyLong_IsCompact(op);
+    return _PyLong_IsCompact((PyLongObject*)op);
 }
 
 #undef PyUnstable_Long_CompactValue
 
 Py_ssize_t
 PyUnstable_Long_CompactValue(const PyLongObject* op) {
-    return _PyLong_CompactValue(op);
+    return _PyLong_CompactValue((PyLongObject*)op);
 }