--- a/memory/build/mozjemalloc.cpp
+++ b/memory/build/mozjemalloc.cpp
@@ -788,16 +788,18 @@ public:
   void SplitRun(arena_run_t* aRun, size_t aSize, bool aLarge, bool aZero);
 
   void TrimRunHead(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize, size_t aNewSize);
 
   void TrimRunTail(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize, size_t aNewSize, bool dirty);
 
   inline void* MallocBinEasy(arena_bin_t* aBin, arena_run_t* aRun);
 
+  void* MallocBinHard(arena_bin_t* aBin);
+
   void Purge(bool aAll);
 
   void HardPurge();
 };
 
 /******************************************************************************/
 /*
  * Data.
@@ -3116,28 +3118,28 @@ arena_t::MallocBinEasy(arena_bin_t* aBin
 
   ret = arena_run_reg_alloc(aRun, aBin);
   MOZ_DIAGNOSTIC_ASSERT(ret);
   aRun->nfree--;
 
   return ret;
 }
 
-/* Re-fill bin->runcur, then call arena_t::MallocBinEasy(). */
-static void *
-arena_bin_malloc_hard(arena_t *arena, arena_bin_t *bin)
+/* Re-fill aBin->runcur, then call arena_t::MallocBinEasy(). */
+void*
+arena_t::MallocBinHard(arena_bin_t* aBin)
 {
-
-	bin->runcur = arena_bin_nonfull_run_get(arena, bin);
-	if (!bin->runcur)
-		return nullptr;
-	MOZ_DIAGNOSTIC_ASSERT(bin->runcur->magic == ARENA_RUN_MAGIC);
-	MOZ_DIAGNOSTIC_ASSERT(bin->runcur->nfree > 0);
-
-	return arena->MallocBinEasy(bin, bin->runcur);
+  aBin->runcur = arena_bin_nonfull_run_get(this, aBin);
+  if (!aBin->runcur) {
+    return nullptr;
+  }
+  MOZ_DIAGNOSTIC_ASSERT(aBin->runcur->magic == ARENA_RUN_MAGIC);
+  MOZ_DIAGNOSTIC_ASSERT(aBin->runcur->nfree > 0);
+
+  return MallocBinEasy(aBin, aBin->runcur);
 }
 
 /*
  * Calculate bin->run_size such that it meets the following constraints:
  *
  *   *) bin->run_size >= min_run_size
  *   *) bin->run_size <= arena_maxclass
  *   *) bin->run_size <= RUN_MAX_SMALL
@@ -3248,17 +3250,17 @@ arena_malloc_small(arena_t *arena, size_
 		    + (ffs((int)(size >> opt_small_max_2pow)) - 2)];
 	}
 	MOZ_DIAGNOSTIC_ASSERT(size == bin->reg_size);
 
 	malloc_spin_lock(&arena->mLock);
 	if ((run = bin->runcur) && run->nfree > 0)
 		ret = arena->MallocBinEasy(bin, run);
 	else
-		ret = arena_bin_malloc_hard(arena, bin);
+		ret = arena->MallocBinHard(bin);
 
 	if (!ret) {
 		malloc_spin_unlock(&arena->mLock);
 		return nullptr;
 	}
 
 	arena->mStats.allocated_small += size;
 	malloc_spin_unlock(&arena->mLock);