Build error: CMake Error at media_driver/media_top_cmake.cmake:92 (add_subdirectory)

[dbermond]

I'm getting the following error when trying to build intel-media-driver git master:

CMake Error at media_driver/media_top_cmake.cmake:92 (add_subdirectory):
  add_subdirectory given source
  "/storage/linux/abs/intel-media-driver-git/src/media-driver/../gmmlib/Source/GmmLib"
  which is not an existing directory.
Call Stack (most recent call first):
  media_driver/CMakeLists.txt:111 (include)


-- LIBVA_DRIVERS_PATH = /usr/lib/dri
-- Configuring incomplete, errors occurred!

• A git bisect shows that the offending commit is 1383ce4.

• I can confirm that it was building fine up until commit 10f382d.

• Complete cmake command and output: https://bpaste.net/show/362d3a855b14.

• Workspace is setted according to the most recent README.md file.

• gmmlib is installed on system. The same error is shown if gmmlib is uninstalled.

System Information:
OS: Arch Linux x86_64
Compiler: gcc 8.2.0
CMake: 3.12.1
intel-media-driver: git master
gmmlib: git master
libva: git master

[yangning1368]

Please help to review PR#301, it would be OK for your compilation.

#301

[dbermond]

@YANGNIN Thank you for the reply.

PR #301 changes only the file README.md. No code is changed on it that can fix this issue. This readme change only instructs to have gmmlib git master installed, which I already have. My installed gmmlib is currently at commit intel/gmmlib@99ff764.

[dvrogozh]

@dbermond : Let me decipher what"[CP] Backout Cl793947 and CL793977(CL#794834)" ( 1383ce4) means. These changes marked with CL#<...> introduced a configuration of media-driver against installed gmmlib, i.e. after these changes the process of building media-driver was:

1. Build and install gmmlib
2. Build media-driver

See #270 (merged as 87fadbe). Since these changes were "backout", read "reverted", we have lost the configuration against installed gmmlib.

So, here is how you would be able to build media driver:

1. Prior to 87fadbe - you should have gmmlib sources along with media-driver sources
2. Starting from 87fadbe and till (not inclusively) 1383ce4 - you can build against installed gmmlib
3. Starting from 1383ce4 - you again need to have gmmlib sources along with media-driver:(

Please, also pay attention that:

1. The most recent pre-release tag (https://github.com/intel/media-driver/releases/tag/intel-media-18.3.pre2) contains switch to dynamic gmmlib #270
2. The intend is to have all next releases or pre-releases containing switch to dynamic gmmlib #270

I.e. the situation described above is temporal and team if working on re-applying #270 before next tags/releases. The reason for the revert was internally detected regressions which, I believe, are not related to media-driver itself.

That's the best I could describe the situation. I hope it helps.

[dvrogozh]

@YANGNIN : I strongly suggest to consider the following:

• If you submit anything to the repository, commit message should clearly state what was changed and why
• Avoid usage of non-standard practices and words in the commit message. Current "Backout" process is absolutely not clear from the perspective of good commit message, community standard practices and even naming of the process. IMHO, you have substituted git-revert! As a result you can reasonably expect that people will not understand what was done.
• Avoid reverting changes depending on the internal state, i.e. avoid situations when media-driver is not affected in any externally visible way, but you still revert changes because of some internal considerations

[dbermond]

@dvrogozh Thank you for your very explanatory comment. It makes it clear to understand what's going on with theses changes in the gmmlib requirement.

Now I can build intel-media-driver with the old cmake command that points to local gmmlib sources, although the actual README.md does not mention it anymore.

[dbermond]

The use of dynamic gmmlib is now enabled again in the current git master branch since September 6, 2018 through commit 63dd4ae. It solves this issue.

I think this issue can be closed.

Thank you.

[dvrogozh]

@dbermond : you were ahead of me tor write this down:). Yes, gmmlib change was re-introduced and now media-driver should be able to properly detect it via pkg-config. Eventually, this will be available in the upcoming 18.3 release.