feat(Cabal): Always pass -pgml to GHC so that linking uses the toolchain Cabal resolved

[zlonast]

Main idea #9801 (comment)

IMHO, cc-options (and ld-options and cpp-options and ...) should be always passed when invoking GHC, similarly as ghc-options should be always used when invoking ghc - regardless of what is the intention of a particular GHC-call. GHC might use or not use the options, Cabal cannot know and should not guess.

  $ cabal build -v3 --with-gcc=$PWD/my-cc-wrapper.sh
  Running: ghc ... -pgmc $PWD/my-cc-wrapper.sh -pgmcxx /usr/bin/g++ ...
- ... link driven by the C compiler from GHC's settings ...
+ Running: ghc ... -pgmc $PWD/my-cc-wrapper.sh -pgmcxx /usr/bin/g++
+          -pgml $PWD/my-cc-wrapper.sh -pgml-supports-no-pie ...

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[TeofilC]

Perhaps @MangoIV has an opinion since he's been working on the linker selection stuff in GHC recently

[MangoIV]

In my opinion, this is not the correct way to do it. GHC bindists should be configured to use a specific C toolchain. A user will inevitably make subtly wrong choices here, that's why we have the configure script.

[MangoIV]

In my opinion, cabal should ask GHC what toolchain it was configured with and then use that, instead of the other way around.

[MangoIV]

This already makes sense if you consider that GHC compiled for some specific backend will not even be able to respect toolchain options found by cabal, e.g. a ghc targeting the JS backend will need the emscripten toolchain.

[zlonast]

@MangoIV As I understand it, we first need to decide how to interact correctly after configuration: #12332

[zlonast]

Also, as I understand it, the -pgml flag should be deprecated, since it has no meaning after configuration?

[zlonast]

I'm closing in favor #12333