Fix Windows build
diff --git a/src/hb-atomic.hh b/src/hb-atomic.hh
index 3ccaf55..545c937 100644
--- a/src/hb-atomic.hh
+++ b/src/hb-atomic.hh
@@ -257,10 +257,10 @@
inline void hb_atomic_int_impl_set (int *AI, int v) { _hb_memory_w_barrier (); *AI = v; }
#endif
#ifndef hb_atomic_int_impl_get
-inline int hb_atomic_int_impl_get (int *AI) { int v = *AI; _hb_memory_r_barrier (); return v; }
+inline int hb_atomic_int_impl_get (const int *AI) { int v = *AI; _hb_memory_r_barrier (); return v; }
#endif
#ifndef hb_atomic_ptr_impl_get
-inline void *hb_atomic_ptr_impl_get (void **P) { void *v = *P; _hb_memory_r_barrier (); return v; }
+inline void *hb_atomic_ptr_impl_get (void ** const P) { void *v = *P; _hb_memory_r_barrier (); return v; }
#endif
