Re: Use newer m4_map_args_{w,sep}

[Paolo Bonzini]

> I suppose it might be possible to make m4_expand tolerant of underquoted # 
> (and 
> also a trailing dnl), by having it append a newline prior to the alternate 
> close-quote handed to _m4_expand, then stripping the newline after the fact, 
> but it seems like a lot of overhead when the correct solution is to properly 
> quote in the first place.  Not many people use # inside AC_DEFINE, in part 
> because you have to use config.h instead of command line (after all, we 
> document that passing # through AC_DEFINE tends to get eaten by Makefile).

There is one famous package that has this problem: Ruby.

http://google.com/codesearch?hl=en&q=AC_DEFINE.*%23+-%23undef+show:we8yX7aPbNs:HuxpWw1qJ6A:PgJFo3MTLGM&sa=N&cd=2&ct=rc&cs_p=ftp://ftp.sunfreeware.com/pub/freeware/SOURCES/ruby-1.8.6.tar.gz&cs_f=ruby-1.8.6/configure.in

While I disagree with Ralf that this kind of incompatibilities are "more
common than we'd like" in Autoconf git, I do think this is a showstopper
for this patch, unfortunately.

Paolo