[gn] Enable stricter build flags

src/heap/spaces.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/spaces.h"
 
 #include <utility>
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
@@ skipping 490 matching lines @@
   }
 
   controller->TakeControl(&reservation);
   return base;
 }
 
 void Page::InitializeAsAnchor(Space* space) {
   set_owner(space);
   set_next_chunk(this);
   set_prev_chunk(this);
-  SetFlags(0, ~0);
+  SetFlags(0, static_cast<uintptr_t>(~0));
   SetFlag(ANCHOR);
 }
 
 MemoryChunk* MemoryChunk::Initialize(Heap* heap, Address base, size_t size,
                                      Address area_start, Address area_end,
                                      Executability executable, Space* owner,
                                      base::VirtualMemory* reservation) {
   MemoryChunk* chunk = FromAddress(base);
 
   DCHECK(base == chunk->address());
@@ skipping 1108 matching lines @@
     while (actual_pages < expected_pages) {
       actual_pages++;
       current_page =
           heap()->memory_allocator()->AllocatePage<MemoryAllocator::kPooled>(
               Page::kAllocatableMemory, this, executable());
       if (current_page == nullptr) return false;
       DCHECK_NOT_NULL(current_page);
       current_page->InsertAfter(anchor());
       current_page->ClearLiveness();
       current_page->SetFlags(anchor()->prev_page()->GetFlags(),
-                             Page::kCopyAllFlags);
+                             static_cast<uintptr_t>(Page::kCopyAllFlags));
       heap()->CreateFillerObjectAt(current_page->area_start(),
                                    static_cast<int>(current_page->area_size()),
                                    ClearRecordedSlots::kNo);
     }
   }
   return true;
 }
 
 AllocationInfo LocalAllocationBuffer::Close() {
   if (IsValid()) {
@@ skipping 436 matching lines @@
 }
 
 void SemiSpace::RemovePage(Page* page) {
   if (current_page_ == page) {
     current_page_ = page->prev_page();
   }
   page->Unlink();
 }
 
 void SemiSpace::PrependPage(Page* page) {
-  page->SetFlags(current_page()->GetFlags(), Page::kCopyAllFlags);
+  page->SetFlags(current_page()->GetFlags(),
+                 static_cast<uintptr_t>(Page::kCopyAllFlags));
   page->set_owner(this);
   page->InsertAfter(anchor());
   pages_used_++;
 }
 
 void SemiSpace::Swap(SemiSpace* from, SemiSpace* to) {
   // We won't be swapping semispaces without data in them.
   DCHECK_NE(from->anchor_.next_page(), &from->anchor_);
   DCHECK_NE(to->anchor_.next_page(), &to->anchor_);
 
@@ skipping 1173 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8