diff --git a/Parser/node.c b/Parser/node.c
index b26ce61..564bd91 100644
--- a/Parser/node.c
+++ b/Parser/node.c
@@ -91,7 +91,7 @@
     if (current_capacity < 0 || required_capacity < 0)
         return E_OVERFLOW;
     if (current_capacity < required_capacity) {
-        if (required_capacity > PY_SIZE_MAX / sizeof(node)) {
+        if ((size_t)required_capacity > PY_SIZE_MAX / sizeof(node)) {
             return E_NOMEM;
         }
         n = n1->n_child;
diff --git a/Python/compile.c b/Python/compile.c
index 0fc9186..a7ddc5a 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -3899,7 +3899,7 @@
     a->a_lnotab = PyBytes_FromStringAndSize(NULL, DEFAULT_LNOTAB_SIZE);
     if (!a->a_lnotab)
         return 0;
-    if (nblocks > PY_SIZE_MAX / sizeof(basicblock *)) {
+    if ((size_t)nblocks > PY_SIZE_MAX / sizeof(basicblock *)) {
         PyErr_NoMemory();
         return 0;
     }