Fix the build on Windows.

src/mem/largealloc.h

@@ -110,7 +110,7 @@ namespace snmalloc
           if (slab->get_kind() != Decommitted)
           {
             PAL::notify_not_using(
-              static_cast<char*>(slab) + OS_PAGE_SIZE, decommit_size);
+              pointer_offset(slab, OS_PAGE_SIZE), decommit_size);
           }
           // Once we've removed these from the stack, there will be no
           // concurrent accesses and removal should have established a

src/mem/pagemap.h

@@ -78,7 +78,7 @@ namespace snmalloc
       (INDEX_LEVELS * BITS_PER_INDEX_LEVEL) + BITS_FOR_LEAF + GRANULARITY_BITS;
 
     // Value used to represent when a node is being added too
-    static constexpr InvalidPointer<1> LOCKED_ENTRY;
+    static constexpr InvalidPointer<1> LOCKED_ENTRY{};
 
     struct Leaf
     {