diff --git a/src/jit/dis_ppc.lua b/src/jit/dis_ppc.lua
index 30eb3978..d497ac78 100644
--- a/src/jit/dis_ppc.lua
+++ b/src/jit/dis_ppc.lua
@@ -38,7 +38,7 @@ local map_crops = {
 local map_rlwinm = setmetatable({
   shift = 0, mask = -1,
 },
-{ __index = function(t, x)
+{ __index = function(_, x)
     local rot = band(rshift(x, 11), 31)
     local mb = band(rshift(x, 6), 31)
     local me = band(rshift(x, 1), 31)
@@ -166,7 +166,7 @@ local map_ext = setmetatable({
 
   [539] = "srdRR~R.",
 },
-{ __index = function(t, x)
+{ __index = function(_, x)
     if band(x, 31) == 15 then return "iselRRRC" end
   end
 })