diff --git a/js/src/gc/AllocKind.h b/js/src/gc/AllocKind.h
index 8c7755f85e3a..178976a7c070 100644
--- a/js/src/gc/AllocKind.h
+++ b/js/src/gc/AllocKind.h
@@ -66,7 +66,7 @@ namespace gc {
     D(FAT_INLINE_ATOM,     String,       js::FatInlineAtom, js::FatInlineAtom, true,   false,  true) \
     D(ATOM,                String,       js::NormalAtom,    js::NormalAtom,    true,   false,  true) \
     D(SYMBOL,              Symbol,       JS::Symbol,        JS::Symbol,        true,   false,  false) \
-    D(BIGINT,              BigInt,       JS::BigInt,        JS::BigInt,        true,   false,  false) \
+    D(BIGINT,              BigInt,       JS::BigInt,        JS::BigInt,        true,   false,  true) \
     D(JITCODE,             JitCode,      js::jit::JitCode,  js::jit::JitCode,  false,  false,  false) \
     D(SCOPE,               Scope,        js::Scope,         js::Scope,         true,   false,  true) \
     D(REGEXP_SHARED,       RegExpShared, js::RegExpShared,  js::RegExpShared,  true,   false,  true)
diff --git a/js/src/gc/GC.cpp b/js/src/gc/GC.cpp
index efdc8d1c18e6..8b2933bc2636 100644
--- a/js/src/gc/GC.cpp
+++ b/js/src/gc/GC.cpp
@@ -2453,6 +2453,7 @@ void MovingTracer::onScopeEdge(Scope** scopep) { updateEdge(scopep); }
 void MovingTracer::onRegExpSharedEdge(RegExpShared** sharedp) {
   updateEdge(sharedp);
 }
+void MovingTracer::onBigIntEdge(BigInt** bip) { updateEdge(bip); }
 
 void Zone::prepareForCompacting() {
   FreeOp* fop = runtimeFromMainThread()->defaultFreeOp();
diff --git a/js/src/gc/GCInternals.h b/js/src/gc/GCInternals.h
index c95d49c2a0aa..484cc65dccd6 100644
--- a/js/src/gc/GCInternals.h
+++ b/js/src/gc/GCInternals.h
@@ -161,6 +161,7 @@ struct MovingTracer : JS::CallbackTracer {
   void onBaseShapeEdge(BaseShape** basep) override;
   void onScopeEdge(Scope** basep) override;
   void onRegExpSharedEdge(RegExpShared** sharedp) override;
+  void onBigIntEdge(BigInt** bip) override;
   void onChild(const JS::GCCellPtr& thing) override {
     MOZ_ASSERT(!thing.asCell()->isForwarded());
   }
diff --git a/js/src/gc/Marking-inl.h b/js/src/gc/Marking-inl.h
index 83fb0fb18b8a..0d3adab6cc89 100644
--- a/js/src/gc/Marking-inl.h
+++ b/js/src/gc/Marking-inl.h
@@ -62,6 +62,7 @@ struct MightBeForwarded {
                             mozilla::IsBaseOf<Shape, T>::value ||
                             mozilla::IsBaseOf<BaseShape, T>::value ||
                             mozilla::IsBaseOf<JSString, T>::value ||
+                            mozilla::IsBaseOf<JS::BigInt, T>::value ||
                             mozilla::IsBaseOf<JSScript, T>::value ||
                             mozilla::IsBaseOf<js::LazyScript, T>::value ||
                             mozilla::IsBaseOf<js::Scope, T>::value ||