Support ghc-9.12.*

[philderbeast]

I'm trying out -XMultilineStrings in cabal-testsuite and struck this warning, having installed ghc-9.12.1 with ghcup:

+Warning: Unknown/unsupported 'ghc' version detected (Cabal 3.15.0.0 supports 'ghc' version < 9.12):
/.../.ghcup/bin/ghc is version <GHCVER>

This pull request is the same as #9928 (that adds support for ghc-9.10.*) but bumps the GHC version once more.

---

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[ulysses4ever]

Thanks!

[Mikolaj]

I wonder if this bump is already on branch 3.14, given that cabal-install 3.14.1.0 is a companion release to GHC 9.12.1.

[ffaf1]

Thanks.

I forgot: should we have done this during release time?

[ulysses4ever]

I forgot: should we have done this during release time?

wow, that may justify 3.14.2...

[ulysses4ever]

Doesn't seem like 3.14 has this change:

see https://github.com/haskell/cabal/blob/3.14/Cabal/src/Distribution/Simple/GHC.hs and in particular:

cabal/Cabal/src/Distribution/Simple/GHC.hs

Lines 167 to 174 in aee57e8

	-- Cabal currently supports ghc >= 7.0.1 && < 9.12
	-- ... and the following odd development version
	unless (ghcVersion < mkVersion [9, 12]) $
	warn verbosity $
	"Unknown/unsupported 'ghc' version detected "
	++ "(Cabal "
	++ prettyShow cabalVersion
	++ " supports 'ghc' version < 9.12): "

[philderbeast]

Label merge+no rebase is necessary when the pull request is from an organisation.

[geekosaur]

@mergify backport 3.14

[mergify]

backport 3.14

✅ Backports have been created

• #10671 Backport #10656: Support ghc-9.12.* has been created for branch 3.14

[geekosaur]

@mergify backport 3.14.1.1

[mergify]

backport 3.14.1.1

✅ Backports have been created

• #10672 Backport #10656: Support ghc-9.12.* has been created for branch 3.14.1.1