Bug#341263: autoconf doesn't realise its cache is out of date when included files change
Ben Pfaff wrote: There are at least two different issues here. The first is simply that Autoconf renames sinclude to m4_sinclude via M4sugar. I don't know why bare sinclude works for you; it does not work for me. If I replace sinclude by m4_sinclude, I can reproduce your problem. Odd... When the first issue is cleared up, the second arises. This is what you are pointing out: m4_sinclude does not do dependency tracking. The way to fix this would be to make autom4te record which optional (m4_sinclude) dependencies were present or absent on the last run, so that it could update the target only if that state changed. My advice would be to use m4_include instead of m4_sinclude if possible. I'm using sinclude here to include configure.in fragments from plug-ins into the main configure.in. Some plugins are simple enough not to need any configure.in checks, so they don't have a fragment. I suppose I could force them all to have an empty file and use include, but. (In practice the workaround I've adopted is that we unconditionally blow away the autom4te.cache before running autoconf since we don't run autoconf unless configure.in or a fragment changed, making the cache pretty useless.) Otherwise, if you'd like to implement the above behavior and submit a patch to me, I'd be happy to review it, include it in the Debian Autoconf, and submit to upstream. I might have a look at this (although the internals of autoconf are largely a mystery to me). -- PMM -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Bug#341263: autoconf doesn't realise its cache is out of date when included files change
[EMAIL PROTECTED] writes: Package: autoconf Version: 2.59a-3 Watch: ---begin--- zircon$ mkdir test zircon$ cd test zircon$ cat configure.in AC_PREREQ(2.50) AC_INIT(test,1) AC_CHECK_FUNCS(wombat) sinclude(conf2.in) AC_OUTPUT() zircon$ autoconf zircon$ grep wombat configure for ac_func in wombat zircon$ grep baboon configure zircon$ cat conf2.in AC_CHECK_FUNCS(baboon) zircon$ autoconf zircon$ grep baboon configure zircon$ rm -rf autom4te.cache/ zircon$ autoconf zircon$ grep baboon configure for ac_func in baboon ---endit--- There are at least two different issues here. The first is simply that Autoconf renames sinclude to m4_sinclude via M4sugar. I don't know why bare sinclude works for you; it does not work for me. If I replace sinclude by m4_sinclude, I can reproduce your problem. When the first issue is cleared up, the second arises. This is what you are pointing out: m4_sinclude does not do dependency tracking. This is because, unless Autom4te actually records the dependencies of a traced file that existed at the time, it has to assume that a dependency that does not exist may be missing because the file that included it was changed to no longer include it. Thus, a missing dependency always triggers an update. This interacts badly with m4_sinclude, which doesn't yield an error if the dependency is missing. The way to fix this would be to make autom4te record which optional (m4_sinclude) dependencies were present or absent on the last run, so that it could update the target only if that state changed. Autoconf 2.59 doesn't have any such logic, and a look at Autoconf CVS shows that it hasn't been added there either. My advice would be to use m4_include instead of m4_sinclude if possible. Otherwise, if you'd like to implement the above behavior and submit a patch to me, I'd be happy to review it, include it in the Debian Autoconf, and submit to upstream. (I have little interest in implementing this behavior myself.) -- Ben Pfaff email: [EMAIL PROTECTED] web: http://benpfaff.org -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Bug#341263: autoconf doesn't realise its cache is out of date when included files change
Package: autoconf Version: 2.59a-3 Watch: ---begin--- zircon$ mkdir test zircon$ cd test zircon$ cat configure.in AC_PREREQ(2.50) AC_INIT(test,1) AC_CHECK_FUNCS(wombat) sinclude(conf2.in) AC_OUTPUT() zircon$ autoconf zircon$ grep wombat configure for ac_func in wombat zircon$ grep baboon configure zircon$ cat conf2.in AC_CHECK_FUNCS(baboon) zircon$ autoconf zircon$ grep baboon configure zircon$ rm -rf autom4te.cache/ zircon$ autoconf zircon$ grep baboon configure for ac_func in baboon ---endit--- Notice that the first autoconf creates a configure script which has a check for 'wombat' but not 'baboon' (correctly, because at this point conf2.in doesn't exist). We then create conf2.in, but rerunning autoconf has no effect -- this is a bug. Blowing away the autom4te.cache causes autoconf to do the right thing and update the configure script so it includes the new check. This seems to happen both for newly created included files (as in this test sequence) and where a preexisting include file is updated. -- PMM -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
