4.19.1.1: rpmbuild --undefine foo is not working

[kloczek]

I know that this option is not mentioned anywhere in documentation however IMO it should be present to be able not only define from command line macro using --define foo but as well undefine it if it is present in global or spec macros.
So this is I've decided to raise this not as RFE but issue ticket.

More interesting is that on use rpmbuild --undefine foo rpmbuild do not fails with message informing that it is is unsupported option.
I'm not 100% how --undefine option is recognised but looks like some parts or rpm command line parsing are involved.
I made two test specs to expose that

test-define.spec

Summary:        test --define
Name:           test-define
Version:        1
License:        foo
Release:        2%{?dist}

%description
Test --define.

%prep

%if 0%{?test}
echo "test defined"
%endif

%check
echo "%{name} package has no test suite"

%files

test-undefine.spec

%define         test    1

Summary:        test --undefine
Name:           test-undefine
Version:        1
License:        foo
Release:        2%{?dist}

%description
Test --undefine.

%prep

%if 0%{?test}
echo "test defined"
%endif

%check
echo "%{name} package has no test suite"

%files

And here are results:

[tkloczko@pers-jacek SPECS]$ rpmbuild -bp test-define.spec
warning: source_date_epoch_from_changelog set but %changelog is missing
Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.ySytzr
+ umask 022
+ cd /home/tkloczko/rpmbuild/BUILD
+ RPM_EC=0
++ jobs -p
+ exit 0

RPM build warnings:
    source_date_epoch_from_changelog set but %changelog is missing
[tkloczko@pers-jacek SPECS]$ rpmbuild -bp test-define.spec --define "test 1"
warning: source_date_epoch_from_changelog set but %changelog is missing
Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.PANGwI
+ umask 022
+ cd /home/tkloczko/rpmbuild/BUILD
+ echo 'test defined'
test defined
+ RPM_EC=0
++ jobs -p
+ exit 0

RPM build warnings:
    source_date_epoch_from_changelog set but %changelog is missing

So it works as expected.
And here is --undefine test

[tkloczko@pers-jacek SPECS]$ rpmbuild -bp test-undefine.spec
warning: source_date_epoch_from_changelog set but %changelog is missing
Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.GM3NF2
+ umask 022
+ cd /home/tkloczko/rpmbuild/BUILD
+ echo 'test defined'
test defined
+ RPM_EC=0
++ jobs -p
+ exit 0

RPM build warnings:
    source_date_epoch_from_changelog set but %changelog is missing
[tkloczko@pers-jacek SPECS]$ rpmbuild -bp test-undefine.spec --undefine test
warning: source_date_epoch_from_changelog set but %changelog is missing
Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.2kdiZT
+ umask 022
+ cd /home/tkloczko/rpmbuild/BUILD
+ echo 'test defined'
test defined
+ RPM_EC=0
++ jobs -p
+ exit 0

RPM build warnings:
    source_date_epoch_from_changelog set but %changelog is missing

So --undefine as cmd param is recognised however second case is not handled as expected.
I'm almost sure that fixing that could be one one or two code lines change .. however cannot locate that.
May I ask for help? 🤔

[pmatilai]

--define and --undefine execute long before the spec is parsed, so while they can affect the way a spec is parsed, neither can affect a macro defined inside a spec.

[kloczek]

--define and --undefine execute long before the spec is parsed, so while they can affect the way a spec is parsed, neither can affect a macro defined inside a spec.

Please have look one more time on my examples.
--define IS working and at the same time --undefine IS NOT working so it cannot be matter of when something is parsed.

[pmatilai]

No, read what I wrote more carefully. Neither --define or --undefine can affect a macro defined inside a spec.
Both can affect the parse, and cause things to be defined or undefined, but only wrt macros that are defined before the macro is parsed.

[kloczek]

No, read what I wrote more carefully. Neither --define or --undefine can affect a macro defined inside a spec.
Both can affect the parse, and cause things to be defined or undefined, but only wrt macros that are defined before the macro is parsed.

Please have look ONE MORE time on specs example which disproves what you just wrote.

[pmatilai]

No, it doesn't.

[kloczek]

No, it doesn't.

Can you show your executios of commands executions which I've provided?
Did you try to reproduce what I've done? 🤔

[mlschroe]

Your "test-define" example is also not working like you expect. If you add

%define test 2

at the top of the specfile and add "%test" to your echo statement, you'll see that it echos "2" even if you call rpmbuild with --define "test 1".

Basically --define and --undefine work similar to adding define/undefine to the top of the spec file. So it is not possible to change a %define that comes later on.