Remove plutus-ghc-stub (#6514)

.gitattributes

@@ -1,6 +1,5 @@
 # linguist gets confused by PIR files, and thinks they make up a lot of our source!
 *.pir linguist-detectable=false
-stubs/plutus-ghc-stub/** linguist-vendored=true
 # Large HTML files inside 'notes' are dominating our repoistory language
 # estimate.
 notes/**/*.html linguist-documentation

cabal.project

@@ -29,7 +29,6 @@ packages: cardano-constitution
           plutus-tx-plugin
           plutus-tx-test-util
           prettyprinter-configurable
-          stubs/plutus-ghc-stub
           doc/docusaurus/docusaurus-examples.cabal
 
 -- We never, ever, want this.
@@ -60,11 +59,6 @@ if impl(ghc < 9.0) || os(windows)
   allow-older: plutus-cert:base
 
 if os(windows)
-   -- When cross compiling we don't have a `ghc` package, so use
-  -- the `plutus-ghc-stub` package instead.
-  package plutus-tx-plugin
-    flags: +use-ghc-stub
-
   -- Exclude tests that use `doctest`.  They will not work for
   -- cross compilation and `cabal` will not be able to make a plan.
   package prettyprinter-configurable

plutus-tx-plugin/plutus-tx-plugin.cabal

@@ -50,11 +50,6 @@ common os-support
   if (impl(ghcjs) || os(windows))
     buildable: False
 
-flag use-ghc-stub
-  description: Use the `plutus-ghc-stub` package instead of `ghc`.
-  default:     False
-  manual:      True
-
 library
   import:          lang, ghc-version-support, os-support
   hs-source-dirs:  src
@@ -85,6 +80,7 @@ library
     , either
     , extra
     , flat                                  ^>=0.6
+    , ghc
     , lens
     , mtl
     , plutus-core:{plutus-core, plutus-ir}  ^>=1.34
@@ -94,14 +90,6 @@ library
     , text
     , uniplate
 
-  if flag(use-ghc-stub)
-    build-depends: plutus-ghc-stub
-    ghc-options:
-      -Wno-unused-packages -Wno-unused-imports -Wno-overlapping-patterns
-
-  else
-    build-depends: ghc
-
 executable gen-plugin-opts-doc
   import:           lang, ghc-version-support, os-support
   main-is:          GeneratePluginOptionsDoc.hs
@@ -121,10 +109,6 @@ executable gen-plugin-opts-doc
 
 test-suite plutus-tx-plugin-tests
   import:             lang, ghc-version-support, os-support
-
-  if flag(use-ghc-stub)
-    buildable: False
-
   type:               exitcode-stdio-1.0
   hs-source-dirs:     test
   main-is:            Spec.hs