Cabal: Take into account compilerBuildWay when computing final library ways

[mpickering]

In the profiling dynamic patch I made a mistake when computing the needed ways for a build.

When building an executable, the Haskell modules need to be built

• For the final link way
• For the build way of the compiler if TH is enabled

Before this patch, the modules were being built for all the configured library ways, which built modules in more configurations than the previous version of Cabal.

Fixes #10418

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[geekosaur]

Backportable to 3.14 but not 3.12.

[alt-romes]

Great find. Thanks for the fix.

[geekosaur]

Does this need to be expedited?

[wz1000]

Yes, this needs to be backported to the 3.14 branch too.

[geekosaur]

@mergify backport 3.14

[mergify]

backport 3.14

✅ Backports have been created

• #10422 Cabal: Take into account compilerBuildWay when computing final library ways (backport #10419) has been created for branch 3.14

[geekosaur]

Figured that. It's embarked now.

[Kleidukos]

@Mergifyio backport 3.12

[mergify]

backport 3.12

✅ Backports have been created

• #10423 Cabal: Take into account compilerBuildWay when computing final library ways (backport #10419) has been created for branch 3.12 but encountered conflicts

[geekosaur]

Repeating here: this can't be backported to 3.12 because it's a modification to #9900, which changed the Cabal spec version to 3.13.

[Mikolaj]

Yes, this needs to be backported to the 3.14 branch too.

@wz1000: just to clarify, in our cabal maintainers jargon "expedited" means "merged without waiting the normal 2 days for all interested devs to find time to review and discuss". I believe this patch did not need to be expedited and there was probably a miscommunication of expedited vs. backported.

[geekosaur]

I understood it to be "yes, and…". I already knew it was destined for backporting since it's needed for 9.12.1.