Fix gcc compile error

Bug: v8:8126

R=sattlerf@google.com
CC=jgruber@chromium.org, titzer@chromium.org

Change-Id: I32ec94fd913def346d1e783b2ffd0ec7d16e5df5
Reviewed-on: https://chromium-review.googlesource.com/1203730Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55600}

src/label.h

@@ -32,8 +32,8 @@ class Label {
 // In debug builds, the old Label has to be cleared in order to avoid a DCHECK
 // failure in it's destructor.
 #ifdef DEBUG
-  Label(Label&& other) { *this = std::move(other); }
-  Label& operator=(Label&& other) {
+  Label(Label&& other) V8_NOEXCEPT { *this = std::move(other); }
+  Label& operator=(Label&& other) V8_NOEXCEPT {
     pos_ = other.pos_;
     near_link_pos_ = other.near_link_pos_;
     other.Unuse();
@@ -41,8 +41,8 @@ class Label {
     return *this;
   }
 #else
-  Label(Label&&) = default;
-  Label& operator=(Label&&) = default;
+  Label(Label&&) V8_NOEXCEPT = default;
+  Label& operator=(Label&&) V8_NOEXCEPT = default;
 #endif
 #endif
 

src/wasm/baseline/liftoff-compiler.cc

@@ -63,9 +63,11 @@ constexpr LoadType::LoadTypeValue kPointerLoadType =
 // thus store the label on the heap and keep a unique_ptr.
 class MovableLabel {
  public:
-  Label* get() { return label_.get(); }
+  MOVE_ONLY_NO_DEFAULT_CONSTRUCTOR(MovableLabel);
   MovableLabel() : label_(new Label()) {}
 
+  Label* get() { return label_.get(); }
+
  private:
   std::unique_ptr<Label> label_;
 };
@@ -73,6 +75,8 @@ class MovableLabel {
 // On all other platforms, just store the Label directly.
 class MovableLabel {
  public:
+  MOVE_ONLY_WITH_DEFAULT_CONSTRUCTORS(MovableLabel);
+
   Label* get() { return &label_; }
 
  private: