diff --git a/support/internal/BUILD b/support/internal/BUILD
index 15a947227..1c1c60a72 100644
--- a/support/internal/BUILD
+++ b/support/internal/BUILD
@@ -16,6 +16,7 @@ cc_library(
         "slot.h",
     ],
     compatible_with = ["//buildenv/target:non_prod"],
+    copts = ["-Wshadow"],
     visibility = [
         "//visibility:public",
     ],
diff --git a/support/internal/slot.h b/support/internal/slot.h
index 4374ed6f5..0d219d856 100644
--- a/support/internal/slot.h
+++ b/support/internal/slot.h
@@ -146,7 +146,7 @@ class Slot<std::array<UT, S>> {
   using T = std::array<UT, S>;
   Slot() {}
   explicit constexpr Slot(T&& x) {
-    if constexpr (requires(UT x) { UT(UnsafeRelocateTag{}, std::move(x)); }) {
+    if constexpr (requires(UT t) { UT(UnsafeRelocateTag{}, std::move(t)); }) {
       memcpy(value_.data(), x.data(), sizeof(UT) * S);
     } else {
       value_ = std::move(x);