Re: reduce forks during autoconf

[Bruno Haible]

Eric Blake wrote:
> for this particular usage, I don't think we will ever use
> AC_REPLACE_FUNC with a file name that falls in this category.

Yes, and the used of prefixed identifiers (prefix "AC_", "gl_" etc.) for
active macros pretty much excludes that any file name or function name gets
active in the gl_LIBSOURCES_LIST.

Btw, does the use of m4_append_uniq cause quadratic runtime? I.e. when
there are n invocations of AC_LIBSOURCES, will the time spent in the
m4_append_uniq calls be O(n²) total? Would it be O(n) total if m4_append was
used instead?

Bruno