diff --git a/bin/lean-gdb.py b/bin/lean-gdb.py
index 635efcc456..3bafdcd1a0 100644
--- a/bin/lean-gdb.py
+++ b/bin/lean-gdb.py
@@ -46,7 +46,7 @@ class LeanExprPrinter:
 
 
     def __init__(self, val):
-        self.kind = val['m_ptr']['m_kind']
+        self.kind = int(val['m_ptr']['m_kind'])
         subtype = gdb.lookup_type(LeanExprPrinter.expr_kinds[self.kind][0])
         self.val = val['m_ptr'].cast(subtype.pointer()).dereference()