diff --git a/third_party/blink/public/platform/cross_variant_mojo_util.h b/third_party/blink/public/platform/cross_variant_mojo_util.h
index dee0b95..0c83580 100644
--- a/third_party/blink/public/platform/cross_variant_mojo_util.h
+++ b/third_party/blink/public/platform/cross_variant_mojo_util.h
@@ -124,7 +124,7 @@ class CrossVariantMojoAssociatedReceiver {
   ~CrossVariantMojoAssociatedReceiver() = default;
 
   CrossVariantMojoAssociatedReceiver(
-      CrossVariantMojoAssociatedReceiver&&) noexcept = default;
+      CrossVariantMojoAssociatedReceiver&&) = default;
   CrossVariantMojoAssociatedReceiver& operator=(
       CrossVariantMojoAssociatedReceiver&&) noexcept = default;
 
@@ -155,7 +155,7 @@ class CrossVariantMojoAssociatedRemote {
   ~CrossVariantMojoAssociatedRemote() = default;
 
   CrossVariantMojoAssociatedRemote(
-      CrossVariantMojoAssociatedRemote&&) noexcept = default;
+      CrossVariantMojoAssociatedRemote&&) = default;
   CrossVariantMojoAssociatedRemote& operator=(
       CrossVariantMojoAssociatedRemote&&) noexcept = default;
 
diff --git a/base/containers/flat_map.h b/base/containers/flat_map.h
index ed82c5d..1af6b40 100644
--- a/base/containers/flat_map.h
+++ b/base/containers/flat_map.h
@@ -202,7 +202,7 @@ class flat_map : public ::base::internal::flat_tree<
   ~flat_map() = default;
 
   flat_map& operator=(const flat_map&) = default;
-  flat_map& operator=(flat_map&&) = default;
+  flat_map& operator=(flat_map&&) noexcept = default;
   // Takes the first if there are duplicates in the initializer list.
   flat_map& operator=(std::initializer_list<value_type> ilist);
 
diff --git a/base/containers/flat_tree.h b/base/containers/flat_tree.h
index 9412ff6..8ecc1fa 100644
--- a/base/containers/flat_tree.h
+++ b/base/containers/flat_tree.h
@@ -125,7 +125,7 @@ class flat_tree {
   // Assume that move assignment invalidates iterators and references.
 
   flat_tree& operator=(const flat_tree&);
-  flat_tree& operator=(flat_tree&&);
+  flat_tree& operator=(flat_tree&&) noexcept;
   // Takes the first if there are duplicates in the initializer list.
   flat_tree& operator=(std::initializer_list<value_type> ilist);
 
@@ -519,7 +519,7 @@ auto flat_tree<Key, Value, GetKeyFromValue, KeyCompare>::operator=(
 
 template <class Key, class Value, class GetKeyFromValue, class KeyCompare>
 auto flat_tree<Key, Value, GetKeyFromValue, KeyCompare>::operator=(flat_tree &&)
-    -> flat_tree& = default;
+    noexcept -> flat_tree& = default;
 
 template <class Key, class Value, class GetKeyFromValue, class KeyCompare>
 auto flat_tree<Key, Value, GetKeyFromValue, KeyCompare>::operator=(