Bug 15010

Summary: native.bbclass is unable to clear unconditional overrides during dependency rewriting
Product: [Build System, Metadata & Runtime] BitBake Reporter: Enrico Jorns <ejo>
Component: bitbakeAssignee: Richard Purdie <richard.purdie>
Status: RESOLVED FIXED QA Contact:
Severity: normal    
Priority: Medium+ CC: ejo, poky.bs.watcher, poky.watcher, randy.macleod, yocto
Version: unspecified   
Target Milestone: 4.2 M4   
Hardware: All   
OS: Multiple   
Whiteboard:
OS type for building Yocto: --- Type of Regression: ---
Verified: Documentation change: Don't know

Description Enrico Jorns 2023-01-18 11:17:37 UTC 
When using

  DEPENDS:append = " something"

in a recipe that uses BBCLASSEXTED += "native", the generated DEPENDS list (after parsing the -native variant) will contain both "something-native" as well as "something".

(The latter is then an unexpected target dependency in a -native recipe.)

What should happen instead is that the override (:append) gets cleared during `map_dependencies()` of native.bbclass. Instead, it is applied twice (once during native mapping, and again at the finalization of DEPENDS).

That the appends are not cleared is caused by 

   d.setVar(varname, " ".join(newdeps), parsing=True)

being called with 'parsing=True' introduced by https://git.yoctoproject.org/poky/commit/meta/classes/native.bbclass?id=c4257ed8b1040a5a0e9a95846d81961741239116.

While not clearing overrides is valid for *conditional* overrides, it is not for *unconditional* ones.

However, at the moment there is no bitbake API allowing us to differentiate this.

One possible solution to this mentioned by RP in #yocto is implementing 'filters' as proposed by JPEW: https://git.yoctoproject.org/poky-contrib/log/?h=jpew/bb-filters
Comment 1 Richard Purdie 2023-01-20 12:50:12 UTC 
I made some tests and it looks like for whatever reason we can now remove the parsing=True. I'll send a patch. Ultimately it would be better to switch to some filtering mechanism but that is for another day.