Use bool literals instead of 0/1.
diff --git a/src/hb-coretext.cc b/src/hb-coretext.cc
index aa3921a..9f7745d 100644
--- a/src/hb-coretext.cc
+++ b/src/hb-coretext.cc
@@ -643,7 +643,7 @@
   CFStringRef string_ref = nullptr;
   CTLineRef line = nullptr;
 
-  if (0)
+  if (false)
   {
 resize_and_retry:
     DEBUG_MSG (CORETEXT, buffer, "Buffer resize");
@@ -1054,7 +1054,7 @@
      *
      * https://crbug.com/419769
      */
-    if (0)
+    if (false)
     {
       /* Make sure all runs had the expected direction. */
       bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);