>>> Also, if only one argument is given, won't this do an AC_SUBST([]) ? >> Yes. And I thought it was a no-op (that's why I AC_SUBSTed WARN_CFLAGS >> separately), but it gives an error. > > Should AS_LITERAL_IF be taught to treat the empty argument as non-literal?
No, absolutely. That's the purpose of things such as AS_IDENTIFIER_IF, which is what AC_SUBST uses. I cannot think of a use case for AS_LITERAL_IF on an empty argument, but that's actually because I cannot think right now of a use case for macros accepting empty arguments in general. Paolo
