[gentoo-soc] [xgreenlandforwyy@gmail.com: A question about BUILD_DIR variable in cmake.eclass under EAPI=8]

[gentoo-soc] [xgreenlandforwyy@gmail.com: A question about BUILD_DIR variable in cmake.eclass under EAPI=8]

[wuyy]

Hello all,

Below is the my question about BUILD_DIR variable in cmake.eclass. I
have previously raised it in IRC channel, but did not get it clear, so I
tried to ask the author of cmake.eclass. It seems that Andreas may be
busy recently and I haven't receive a reply, and I'll keep wait. Thus, I
forward this question here so we can discuss it and keep a public
record. If the problem is confirmed to be rather important, I think we
can move the discussion to Gentoo-dev mailing list.

----- Forwarded message from wuyy <xgreenlandforwyy@gmail.com> -----

Date: Fri, 15 Jul 2022 16:49:45 +0800
From: wuyy <xgreenlandforwyy@gmail.com>
To: Andreas Sturmlechner <asturm@gentoo.org>
Subject: A question about BUILD_DIR variable in cmake.eclass under EAPI=8

Hello Andreas,

I'm a student participating in Google Summer of Code this year,
packaging ROCm. I have met a problem when using cmake.eclass, and I'm
not sure whether it should be called a bug or it's just a feature, so I
want to personally ask you, the author of corresponding code.

As I observe the BUILD_DIR variable is no longer globally set in
cmake.eclass under EAPI=8, with this change:

-# ${WORKDIR}/${P}_build.
-: ${BUILD_DIR:=${WORKDIR}/${P}_build}
+# ${CMAKE_USE_DIR}_build (in EAPI-7: ${WORKDIR}/${P}_build).
+[[ ${EAPI} == 7 ]] && : ${BUILD_DIR:=${WORKDIR}/${P}_build}
+# EAPI-8: set inside _cmake_check_build_dir

So I have to use this variable in ebuild after _cmake_check_build_dir
which is inside cmake_src_prepare. That's not an issue in src_prepare.
Also this variable can be used in following phases.  Everything seems
nice, until I begin debugging and polishing src_test.  After a
successful src_compile, I come to the src_test, which has bugs.  I fixed
the bug and rerun ebuild xxx src_test, but it unexpectedly failed,
because BUILD_DIR is empty!

To summarize, BUILD_DIR can live to other phases when phases are
executed in one call, but cannot be kept if the previous steps are
skipped. 

This is not a problem for most scenarios, but it's a bit annoying when
developing and debugging ebuilds. I have to call _cmake_check_build_dir
explicitly before using BUILD_DIR, although src_prepare has been run. I
wonder this may be a bug, but maybe it's designed to work that way for
some reasons I don't know. If you think this is a bug, I can put it on
bugzilla and find a fix to it. Thank you very much!

Best regards 
--
Yiyang Wu

----- End forwarded message -----

-- 

Re: [gentoo-soc] [xgreenlandforwyy@gmail.com: A question about BUILD_DIR variable in cmake.eclass under EAPI=8]

[Michał Górny]

On Sat, 2022-07-16 at 17:38 +0800, wuyy wrote:
> Hello all,
> 
> Below is the my question about BUILD_DIR variable in cmake.eclass. I
> have previously raised it in IRC channel, but did not get it clear, so I
> tried to ask the author of cmake.eclass. It seems that Andreas may be
> busy recently and I haven't receive a reply, and I'll keep wait. Thus, I
> forward this question here so we can discuss it and keep a public
> record. If the problem is confirmed to be rather important, I think we
> can move the discussion to Gentoo-dev mailing list.
> 
> ----- Forwarded message from wuyy <xgreenlandforwyy@gmail.com> -----
> 
> Date: Fri, 15 Jul 2022 16:49:45 +0800
> From: wuyy <xgreenlandforwyy@gmail.com>
> To: Andreas Sturmlechner <asturm@gentoo.org>
> Subject: A question about BUILD_DIR variable in cmake.eclass under EAPI=8
> 
> Hello Andreas,
> 
> I'm a student participating in Google Summer of Code this year,
> packaging ROCm. I have met a problem when using cmake.eclass, and I'm
> not sure whether it should be called a bug or it's just a feature, so I
> want to personally ask you, the author of corresponding code.
> 
> As I observe the BUILD_DIR variable is no longer globally set in
> cmake.eclass under EAPI=8, with this change:
> 
> -# ${WORKDIR}/${P}_build.
> -: ${BUILD_DIR:=${WORKDIR}/${P}_build}
> +# ${CMAKE_USE_DIR}_build (in EAPI-7: ${WORKDIR}/${P}_build).
> +[[ ${EAPI} == 7 ]] && : ${BUILD_DIR:=${WORKDIR}/${P}_build}
> +# EAPI-8: set inside _cmake_check_build_dir
> 
> So I have to use this variable in ebuild after _cmake_check_build_dir
> which is inside cmake_src_prepare. That's not an issue in src_prepare.
> Also this variable can be used in following phases.  Everything seems
> nice, until I begin debugging and polishing src_test.  After a
> successful src_compile, I come to the src_test, which has bugs.  I fixed
> the bug and rerun ebuild xxx src_test, but it unexpectedly failed,
> because BUILD_DIR is empty!
> 
> To summarize, BUILD_DIR can live to other phases when phases are
> executed in one call, but cannot be kept if the previous steps are
> skipped. 
> 
> This is not a problem for most scenarios, but it's a bit annoying when
> developing and debugging ebuilds. I have to call _cmake_check_build_dir
> explicitly before using BUILD_DIR, although src_prepare has been run. I
> wonder this may be a bug, but maybe it's designed to work that way for
> some reasons I don't know. If you think this is a bug, I can put it on
> bugzilla and find a fix to it. Thank you very much!
> 

Can you reproduce while running the test phase via emerge(1)?  Using
ebuild(1) is known to be buggy.

-- 
Best regards,
Michał Górny

Re: [gentoo-soc] [xgreenlandforwyy@gmail.com: A question about BUILD_DIR variable in cmake.eclass under EAPI=8]

[wuyy]

On Sat, Jul 16, 2022 at 12:15:28PM +0200, Michał Górny wrote:
> Can you reproduce while running the test phase via emerge(1)?  Using
> ebuild(1) is known to be buggy.
> 
> -- 
> Best regards,
> Michał Górny
> 
> 

No. Using emerge to perform the test is OK. What I'm concerning is to
skip previous steps and directly run src_test over and over again,
because the compilation takes a long time, and I'm just debugging and
modifying src_test. I did that by calling ebuild(1).

--