In a clean build with 1.17, autom4te.cache/traces.0 says:
...
But in a build with 1.17.90 that has previously been configured with 1.17:
m4_if([$1], [1.17], [],
Unfortunately I have basically zero understanding of autom4te.
(It's part of autoconf.)
So some state from the old build is not being purged when it should be?
I guess, but I have no idea what's going on with autom4te.
Zack, Paul, anyone?
A leaner test case is icon-naming-utils. If I build that with
automake 1.17.0, it works. If I build it _from clean_ with 1.17.90,
it works.
If I build it with 1.17.0 and then autoreconf with 1.17.90, it fails.
Really mysteriously the generated aclocal.m4 has been regenerated
(because the copyright dates are different) but it is missing the
AM_RUN_LOG macro.
Mysterious indeed.
I suppose I could add AC_REQUIRE(AM_TRY_LOG) to the _AM_PROG_TAR macro in
tar.m4. Maybe that would help. But what troubles me is that it seems
none of those basic macros in automake's m4/* have AC_REQUIRE
statements, so why should this be different? Seems weird.
Clearly the problem is happening because of switching the default format
to ustar and hence the non-v7 branch being taken in _AM_PROG_TAR, but
nothing beyond that is clear to me :(.
I'll keep digging when I can. --thanks much, karl.
