RFR: JDK-8248158 Configure fails with autoconf not found even though it's installed

[Galder Zamarreno]

On Mon, Jul 6, 2020 at 10:50 PM Simon Tooke <stooke at redhat.com> wrote:

> (Disclaimer: I am not a reviewer, so this is an opinion, not a review)
>
> I have tested this on Windows and it built without issue, although the
> submit repo should be the final gate.  I'd also like to add my void to
> simply redefining 'WHICH' as it leads to less changes in the source
> code, which would make life easier should this be backported to 11u
> and/or 8u.


So, you would just switch the UTIL_REQUIRE_PROGS call for WHICH to be `type
...` instead?


>
> -Simon
>
> On 2020-07-02 4:22 a.m., Galder Zamarreno wrote:
> > On Thu, Jul 2, 2020 at 12:37 AM Magnus Ihse Bursie <
> > magnus.ihse.bursie at oracle.com> wrote:
> >
> >>
> >> On 2020-07-01 12:05, Galder Zamarreno wrote:
> >>> Using `which` to check whether commands exist can result in confusing
> >>> errors when `which` itself is not installed in the system. This is the
> >> case
> >>> with `autoconf`, where if `autoconf` is present but `which` isn't, the
> >>> build system says that `autoconf` is missing, when in reality it is
> >> `which`
> >>> which is missing. The fix switches autoconf uses of `which` for `type
> -p`
> >>> instead, which is a Bash built-in command.
> >>>
> >>> I've tested the fix with a fedora docker container that had `autoconf`
> >>> installed but `which`. When using `type -p` it correctly detects
> >> `autoconf`
> >>> installed and eventually fails saying that `which` is not installed,
> >> which
> >>> is the expected behaviour.
> >>>
> >>> `which` is still in use in make/autoconf/util_windows.m4. A possible
> >> future
> >>> improvement would be to see if `which` use there could be replaced as
> >> well.
> >>> Eventually, when no `which` uses remain, the presence check for `which`
> >>> could be removed.
> >> I agree that we should replace "which" with "type -p" everywhere. The
> >> best way to do this is probably to replace the value of $WHICH with
> >> "type -p". It's a bash built-in, so we can count on its presence. If you
> >> want to fix that as part of this bug, I'm ok with it, otherwise we
> >> should open a new bug to track this. I think there is also one or two
> >> instances of "command" recently added as (better, but not as good as
> >> "type -p") replacements for which.
> >>
> > I discovered one place in util.m4 where command was being used.
> >
> > There are other places outside of make/ where command is used but I feel
> > those are a bit out of scope here.
> >
> > My main objective is that from a configure perspective, we'd try to
> reduce
> > the number of dependencies needed to build things.
> >
> > I'll send an updated webrev shortly.
> >
> >
> >> /Magnus
> >>> Bug: https://bugs.openjdk.java.net/browse/JDK-8248158
> >>> WebRev:
> >> http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8248158/01/webrev/
> >>> Galder
> >>
>
>