On Tue, Jul 7, 2020 at 1:57 PM Orion Poplawski <orion@xxxxxxxx> wrote: > > On 6/15/20 1:47 PM, Ben Cotton wrote: > > https://fedoraproject.org/wiki/Changes/CMake_to_do_out-of-source_builds > > > > == Summary == > > <code>%cmake</code> macro will be adjusted (<code>-B</code> parameter) > > to use separate build folder (already standardized > > <code>%{_vpath_builddir}</code> macro). Additionally, > > <code>%cmake_build</code>, <code>%cmake_install</code> and > > <code>%ctest</code> macro will be created (and backported to the older > > supported Fedora releases) to perform various operations that are > > commonly used with CMake in a backend-agnostic (Makefiles, Ninja, > > etc.) way. > > > > Packages that will stop building are trivial to fix and will be > > adjusted either by maintainers or change owners. > > > > == Owner == > > * Name: [[User:ignatenkobrain|Igor Raits]], [[User:besser82|Björn > > Esser]], [[User:ngompa|Neal Gompa]] > > * Email: ignatenkobrain@xxxxxxxxxxxxxxxxx, besser82@xxxxxxxxxxxxxxxxx, > > ngompa13@xxxxxxxxx > > > > == Detailed Description == > > Historically, software builds had a singular build configuration and > > required running the build within the project root. Nowadays, there > > are many build modes and options that can be configured in projects, > > different build settings (e.g. compiler flags) / types (release, > > debug) that can be applied and different tools that can be used to > > actually execute builds (compilers like gcc/clang, build job > > schedulers like make/ninja, and so on). Thus, CMake upstream strongly > > discourages users of doing in-source builds and recommends doing > > out-of-source builds. > > > > From <code>cmake.1</code>: > > > > <pre> > > To maintain a pristine source tree, perform an out-of-source build by > > using a separate dedicated build tree. An in-source build in which the > > build tree is placed in the same directory as the source tree is also > > supported, but discouraged. > > </pre> > > > > The other part of the change is introduction of additional macros is > > creation of set of macro that can build, install and run tests in a > > backend-agnostic, vpath-aware (out-of-source, in-source) way. > > > > === Migration === > > > > ==== <code>%cmake</code> + <code>%(make|ninja)_(build|install)</code> ==== > > > > There are multiple paths to complete the migration: > > > > * Add <code>-C "%{_vpath_builddir}"</code> to the <code>%(make|ninja)_*</code> > > * Replace <code>%(make|ninja)_build</code> and > > <code>%(make|ninja)_install</code> with <code>%cmake_build</code> and > > <code>%cmake_install</code> respectively > > * Redefine vpath builddir <code>%global _vpath_builddir .</code> to > > continue performing in-source builds (and optionally converting to the > > <code>%cmake_*</code>) > > > > Depending on the package, one of these options may be used to adapt to > > this change. > > > > ==== <code>%cmake -B builddir</code> + > > <code>%(make|ninja)_(build|install) -C builddir</code> ==== > > > > No changes are needed. > > > > == Benefit to Fedora == > > * Follow CMake upstream recommendations when building packages > > * Brings Fedora package builds more in-line with how upstream projects > > expect them to be built > > * Improve compatibility with other RPM distributions that already do this > > * Support backend-agnostic way of building CMake projects > > > > == Scope == > > * Proposal owners: Implement necessary macros, try to build packages > > that <code>BuildRequires: cmake</code> in a side tag, analyze failures > > and fix the relevant ones (introduced by this change). > > * Other developers: While proposal owners will try to fix all affected > > packages, there might be some cases where package is already FTBFS so > > the fix can't be performed. Other package maintainers will have to fix > > the issue themselves after they fix FTBFS. > > * Release engineering: [https://pagure.io/releng/issue/9524 #9524] > > * Policies and guidelines: CMake page will be adjusted to mention > > newly created macros and the documentation about relevant VPATH macros > > needs to be restructured a bit (they are already documented on the > > Meson page, they need to be moved to the separate page and referenced > > both from CMake and Meson page). > > * Trademark approval: N/A (not needed for this Change) > > > > == Upgrade/compatibility impact == > > Existing packages can (and most likely will) become FTBFS, but > > proposal owners will fix as many Fedora packages as possible. However > > fixing third-party packages is not possible and out of scope. > > Third-party packagers will need to adapt based on the recommendations > > noted in this Change. > > What's the plan for EPEL8/7 compatibility? > I need to talk to EPEL folks about how to handle this. I'm not sure exactly what strategy we should take here. I could override the macros entirely with epel-rpm-macros, which is probably the easiest way to do it. -- 真実はいつも一つ！/ Always, there's only one truth! _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
