Add -Wcast-align
diff --git a/src/Makefile.am b/src/Makefile.am
index f7cf593..b981346 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -8,7 +8,7 @@
 MAINTAINERCLEANFILES =
 DISTCHECK_CONFIGURE_FLAGS = --enable-introspection
 
-# The following warning options are useful for debugging: -Wpadded -Wcast-align
+# The following warning options are useful for debugging: -Wpadded
 #AM_CXXFLAGS =
 
 lib_LTLIBRARIES = libharfbuzz.la