diff --git a/libbuild2-autoconf/libbuild2/autoconf/checks/const.h b/libbuild2-autoconf/libbuild2/autoconf/checks/const.h
index c86d055..af73311 100644
--- a/libbuild2-autoconf/libbuild2/autoconf/checks/const.h
+++ b/libbuild2-autoconf/libbuild2/autoconf/checks/const.h
@@ -1,4 +1,4 @@
-// const
+// const!
 
 /* This check is unusual in that for a positive answer (the compiler supports
    const) we undefine const to allow the compiler to recognize it as a keyword
diff --git a/libbuild2-autoconf/libbuild2/autoconf/checks/inline.h b/libbuild2-autoconf/libbuild2/autoconf/checks/inline.h
index 804fa91..14fbeff 100644
--- a/libbuild2-autoconf/libbuild2/autoconf/checks/inline.h
+++ b/libbuild2-autoconf/libbuild2/autoconf/checks/inline.h
@@ -1,4 +1,4 @@
-// inline
+// inline!
 
 /* This check is unusual in that for a positive answer (the compiler supports
    inline) we undefine inline to allow the compiler to recognize it as a
diff --git a/libbuild2-autoconf/libbuild2/autoconf/checks/volatile.h b/libbuild2-autoconf/libbuild2/autoconf/checks/volatile.h
index ead70a3..99b2829 100644
--- a/libbuild2-autoconf/libbuild2/autoconf/checks/volatile.h
+++ b/libbuild2-autoconf/libbuild2/autoconf/checks/volatile.h
@@ -1,4 +1,4 @@
-// volatile
+// volatile!
 
 /* This check is unusual in that for a positive answer (the compiler supports
    volatile) we undefine volatile to allow the compiler to recognize it as a