For ghc calls pass Cabal's build/ directory after user's src/ directory so that contents of src/ takes precedence

[sergv]

A fix for #8689.

The fix is a one line change that changes order of directories where searches will be searched by the ghc. Cabal's internal build/ directory (e.g. dist-newstyle/build/x86_64-linux/ghc-9.4.4/Cabal-3.9.0.0/build/) now is passed after all source directories specified by the package in order to make sure that if there's a user-supplied file that corresponds to a particular module thet it will never be overshadowed by what's in the cabal's internal build/ directory. Autogenerated modules get written into the internal build/ directory so they have a real chance of shadowing one of user's modules as shown in the linked issue.

Testsing methodology

I built GHC with Cabal that has this patch and run the test. It's tricky to run the added test because it relies on custom setup which can only access Cabal package bundled with GHC.

Custom setup is needed because autogenerated modules with a custom preprocessor (in this case identity preprocessor) are used.

---

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• Patches conform to the coding conventions.
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[Bodigrim]

LGTM!

[Mikolaj]

Looks good, thank you. Please kindly set the merge (squash?) label.

[Mikolaj]

The GHA failure is hacked around; let me rebase to fix CI.

[Mikolaj]

mergify rebase

[Mikolaj]

@mergify rebase

[mergify]

⚠️ This pull request got rebased on behalf of a random user of the organization.
This behavior will change on the 1st February 2023, Mergify will pick the author of the pull request instead.

To get the future behavior now, you can configure bot_account options (e.g.: bot_account: { author } or update_bot_account: { author }.

Or you can create a dedicated github account for squash and rebase operations, and use it in different bot_account options.

[mergify]

rebase

✅ Branch has been successfully rebased

[Mikolaj]

@mergify regresh

[mergify]

regresh

❌ Sorry but I didn't understand the command. Please consult the commands documentation 📚.

[Mikolaj]

@mergify refresh

[mergify]

refresh

✅ Pull request refreshed

[Mikolaj]

silly computer

[Mikolaj]

@mergify rebase

[mergify]

⚠️ This pull request got rebased on behalf of a random user of the organization.
This behavior will change on the 1st February 2023, Mergify will pick the author of the pull request instead.

To get the future behavior now, you can configure bot_account options (e.g.: bot_account: { author } or update_bot_account: { author }.

Or you can create a dedicated github account for squash and rebase operations, and use it in different bot_account options.

[mergify]

rebase

✅ Branch has been successfully rebased

[Mikolaj]

@mergify rebase

[mergify]

⚠️ This pull request got rebased on behalf of a random user of the organization.
This behavior will change on the 1st February 2023, Mergify will pick the author of the pull request instead.

To get the future behavior now, you can configure bot_account options (e.g.: bot_account: { author } or update_bot_account: { author }.

Or you can create a dedicated github account for squash and rebase operations, and use it in different bot_account options.

[mergify]

rebase

✅ Branch has been successfully rebased

[Mikolaj]

@sergv: something locked on hard in CI for this PR. Could you kindly rebase manually? Then we'd run CI and I'd force-merge if needed.

[mergify]

⚠️ This pull request got rebased on behalf of a random user of the organization.
This behavior will change on the 1st February 2023, Mergify will pick the author of the pull request instead.

To get the future behavior now, you can configure bot_account options (e.g.: bot_account: { author } or update_bot_account: { author }.

Or you can create a dedicated github account for squash and rebase operations, and use it in different bot_account options.

[mergify]

rebase

✅ Branch has been successfully rebased

[Mikolaj]

@mergify requeue

[mergify]

requeue

☑️ This pull request is already queued

[Mikolaj]

@mergify unqueue

[mergify]

unqueue

☑️ The pull request is not queued

[Mikolaj]

@mergify requeue

[mergify]

requeue

☑️ This pull request is already queued

[Mikolaj]

doh

[Mikolaj]

@mergify rebase

[mergify]

⚠️ This pull request got rebased on behalf of a random user of the organization.
This behavior will change on the 1st February 2023, Mergify will pick the author of the pull request instead.

To get the future behavior now, you can configure bot_account options (e.g.: bot_account: { author } or update_bot_account: { author }.

Or you can create a dedicated github account for squash and rebase operations, and use it in different bot_account options.

[mergify]

rebase

✅ Branch has been successfully rebased

[Mikolaj]

OK, mergify seems to have unclogged

[Mikolaj]

Phew, finally. @sergv: thank you again!

[andreasabel]

Causing

• Cabal-3.12.0.0 passes include dirs to GHC in a new order #10060