How to control %optflags ?

[lejeczek]

Hi guys.

Would you know if mock can have it set somewhere - beside .spec for a given rpm - so it would be user/env-wide, every time mock runs?
I have %optflags in my .rpmrc but that mock pays no attention to. At the same time --macro-file & --define seem to have no effect - whatever system/os-wide macros say %optflags is, remains - but that also seem to be the case for system's rpmbuild (only .rpmrc overrides it).
I'm on Centos 9 with 6.4 version.
many thanks, L.

[praiskup]

The %optflags are defined in rpmrc (e.g., /usr/lib/rpm/redhat/rpmrc). These are not overriden with ~/.rpmmacros (Mock creates this file).

Check the definition:

$ grep optflags: /usr/lib/rpm/redhat/rpmrc  | grep x86_64_v4
optflags: x86_64_v4 %{__global_compiler_flags} -m64 -march=x86-64-v4 %__cflags_arch_x86_64_common

You should be able to set __global_compiler_flags and __cflags_arch_x86_64_common.

[lejeczek]

Perhaps it's a bit of an edge case - could be just with rhel/centos - where setting those, %__cflags_arch_x86_64 specifically, does not help (%__global_compiler_flags no _common on Centos).
Unless set in ~/.rpmrc in full - gets mangled

-> $ mock -r centos-stream+epel-9-x86_64 --chroot 'rpm --eval %optflags'
...
Start: chroot ['rpm --eval %optflags']
-O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64 -march=x86-64-v3 -mtune=native -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection
Finish: chroot ['rpm --eval %optflags']

notice ! doubled -mtune and the one I need, I set is: native
From what I gathered, superficially, the latter, the last one gcc honours - this might catch many on the hop, it did do that to me.

For @devel - perhaps if not now as a fix then as an enhancement in future release, mock took advantage of ~/.rpmrc ?

[praiskup]

Admittedly, tweaking compiler flags is relatively complicated. The related macros evolve, making it difficult to find a definitive, silver-bullet solution. However, you should be able to find a per-distro specific workaround. Check also this:

$ rpm --eval '%{macrobody:set_build_flags}'

  CFLAGS="${CFLAGS:-%{build_cflags}}" ; export CFLAGS ; 
  CXXFLAGS="${CXXFLAGS:-%{build_cxxflags}}" ; export CXXFLAGS ; 
  FFLAGS="${FFLAGS:-%{build_fflags}}" ; export FFLAGS ; 
  FCFLAGS="${FCFLAGS:-%{build_fflags}}" ; export FCFLAGS ; 
  VALAFLAGS="${VALAFLAGS:-%{build_valaflags}}" ; export VALAFLAGS ;%{?build_rustflags:
  RUSTFLAGS="${RUSTFLAGS:-%{build_rustflags}}" ; export RUSTFLAGS ;} 
  LDFLAGS="${LDFLAGS:-%{build_ldflags}}" ; export LDFLAGS ; 
  LT_SYS_LIBRARY_PATH="${LT_SYS_LIBRARY_PATH:-%_libdir:}" ; export LT_SYS_LIBRARY_PATH ; 
  CC="${CC:-%{__cc}}" ; export CC ; 
  CXX="${CXX:-%{__cxx}}" ; export CXX

Then, of course, you could provide your own package-specific rpmrc file and start using it via BuildRequires.

I personally don't think tweaking Mock to override rpmrc makes much sense (nobody has requested this before). However, if you provide a clean patch, I believe it would be accepted.

[lejeczek]

Override? I'm not sure where I left that impression - but in case I was not clear: to make use of ~/.rpmrc - which is what rpmbuild toolset (& others?) do, no?
~/.rpmrc is meant for that, to be last-man-standing, the decider - how this make little sense?

[praiskup]

~/.rpmrc is meant for that, to be last-man-standing the decider

I don't disagree - I simply don't know. These rpmrc things were always configured by RPM team, and used by RPM.
Package maintainers are not used to touch these things.

• how this make little sense?

This is purely a Mock perspective: There are no (other) users asking for this feature, hence it doesn't make much sense to complicate the code & configuration (considering there is a way to do it differently).

But anyway, if you want to contribute an appropriate patch, I'm sure we'll have time for the review. But it's unlikely we'll have time for writing the code.

[xsuchy]

The other option is to define it in Mock configuration file.

You can set this option:
https://github.com/rpm-software-management/mock/blob/main/mock/docs/site-defaults.cfg#L416

You can store the variable in any configuration file as described at the bottom of https://rpm-software-management.github.io/mock/configuration

[lejeczek]

I did not think it would work in other places since it did not in ~/.config/mock.cfg - only place it works for mock is .spec file - like I said, it is about %optflags, other macros seem to get picked up from user's config but !... this manner, in the end, when it comes to most important bit - gcc - it does not work. (not for me on Centos 9)
Like for mock .spec file, forrpmbuild the ~/rpmrc is the only way - perhaps it is by design or a flow(?) - setting other macros to which %optflags calls out, elsewhere, end up with gcc having doubled -mtune.
No code from me unfortunately - if I could have I'd have, right away, as opposed to here - only admin I do.
Which code/patch addition would be minute I guess, to include - not much complication for users/admins neither, anyone who use mock knows of rpmbuild - which familiarity would also be required if for some reason, ~/rpmrc (if used) was not mentioned in mock man pages.

[xsuchy]

@lejeczek I have a hard time reading your sentences. Can I kindly ask you to slow down and write more clearly?

[praiskup]

I think the point is that %optflags are not defined in a macrofile, but rpmrc (it has a different file syntax). These %optflags can not be overridden using just custom defined macros (hence mock's configuration is out of question).
I thought there's a drop-in directory for rpmrc files, but there isn't (my bet? nobody needed that before, I'd be curious what would RPM developers say for such an RFE).

Still, one should be able to have a custom package shipping /etc/rpmrc (not really "nice" way forward) or provide a custom "patched" version of redhat-rpm-config.

[lejeczek]

@xsuchy I don't know if can write any better, well..
as of now, if one puts all trust on mock for one sees:

-> $ rpm --showrc
...
optflags              : %{__global_compiler_flags} -m64 %{__cflags_arch_x86_64} -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection

one might be mistaken.
If people do not double check compilation process - like I did not initially - they set stuff in ~/.config/mock & assume that __cflags_arch_x86_64 (&| a few other) will set their own -mtune ( which mtune mostly if not exclusively, is the reason we even re-compile ) they will not know that the their mtune is not in effect.
I get -mtune=native -mtune=generic which - from what I understand - tells gcc to do mtune=generic

I originally was asking how to - now I'm suggesting it would be great - to have mock have a way - similarly to rpmbuild and its ~/rpmrc - to arbitrarily set those %optflags for user/env-wide operations.(so doing it in each .spec file is not needed)

With rpm toolset I have:

-> $ cat ~/.rpmmacros
%__cflags_arch_x86_64 -march=x86-64-v3 -mtune=native
-> $ cat ~/.rpmrc 
optflags: x86_64 %{__global_compiler_flags} -m64 %{__cflags_arch_x86_64} -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection

and that is all I need to pay attention to - no need to worry(in this respect with -mtune) for each .spec - compilation works as expected:

-> $ rpm --eval %optflags
-O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64 -march=x86-64-v3 -mtune=native -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection

p.s. I tied to ask about doubled mtune over at https://issues.redhat.com/ - but it was unusable yesterday.
thanks, L.