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

[Galder Zamarreno]

Hi again,

I've got a new webrev for this:
http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8248158/02/webrev/

It further expands `type -p` to replace `command -v` uses. It also replaces
$WHICH usages and removes the check for `which` as well.

I tried Simon's suggestions, but getting that right complicated the patch.

Galder


On Tue, Jul 7, 2020 at 4:31 PM Galder Zamarreno <galder at redhat.com> wrote:

>
>
> 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
>> >>
>>
>>