@@ -22,10 +22,12 @@
 CPPFLAGS="$CPPFLAGS $OBJCPPFLAGS $($OBJFW_CONFIG --cppflags)"
 OBJCFLAGS="$OBJCFLAGS -Wall $($OBJFW_CONFIG --objcflags)"
 LDFLAGS="$LDFLAGS $($OBJFW_CONFIG --ldflags)"
 LIBS="$LIBS $($OBJFW_CONFIG --libs)"
 
+AX_CHECK_COMPILER_FLAGS(-Watomic-properties,
+	[OBJCFLAGS="$OBJCFLAGS -Watomic-properties"])
 AX_CHECK_COMPILER_FLAGS(-Wdocumentation,
 	[OBJCFLAGS="$OBJCFLAGS -Wdocumentation"])
 
 AC_ARG_ENABLE(shared,
 	AS_HELP_STRING([--disable-shared], [do not build shared library]))