Downgrade to GHC 9.12.2 (#587)

* Downgrade to GHC 9.12.2

* Use base 4.21.0.0

Author: vrom911

.github/workflows/ci.yml

@@ -30,7 +30,7 @@ jobs:
           - "9.6.7"
           - "9.8.4"
           - "9.10.3"
-          - "9.12.3"
+          - "9.12.2"
         exclude:
           - os: macOS-latest
             ghc: 9.10.3
@@ -112,28 +112,28 @@ jobs:
       run: |
         cabal test all
 
-    - if: matrix.ghc == '9.12.3'
+    - if: matrix.ghc == '9.12.2'
       name: Build 'cabal-minimal'
       run: |
         cd "summoner-cli/examples/cabal-minimal/"
         echo "packages: ." > cabal.project
         cabal build all
 
-    - if: matrix.ghc == '9.12.3'
+    - if: matrix.ghc == '9.12.2'
       name: Build 'cabal-full'
       run: |
         cd "summoner-cli/examples/cabal-full/"
         echo "packages: ." > cabal.project
         cabal build all
 
-    - if: matrix.ghc == '9.12.3'
+    - if: matrix.ghc == '9.12.2'
       name: Build 'stack-full'
       run: |
         cd "summoner-cli/examples/stack-full/"
         echo "packages: ." > cabal.project
         cabal build all
 
-    - if: matrix.ghc == '9.12.3'
+    - if: matrix.ghc == '9.12.2'
       name: Build 'full-batteries'
       run: |
         cd "summoner-cli/examples/full-batteries/"

CHANGELOG.md

@@ -3,10 +3,11 @@
 `summoner` uses [PVP Versioning][1].
 The changelog is available [on GitHub][2].
 
-# Unreleased
+# 2.1.1.0 – Jan 16, 2026
 
 * [#560](https://github.com/kowainik/summoner/issues/560):
   Allow configurations of the branch name.
+* Roll back to GHC-9.12.2 as 9.12.3 has a major regression.
 
 ## 2.1.0.0 — Jan 6, 2026
 

README.md

@@ -475,7 +475,7 @@ Here is the list of the options that can be configured to suit your needs. If op
 | `fullName`       | Text    | Full name.                                                                                                                                                           |
 | `email`          | Text    | E-mail address.                                                                                                                                                      |
 | `license`        | License | One of: `MIT`, `BSD2`, `BSD3`, `GPL-2`, `GPL-3`, `LGPL-2.1`, `LGPL-3`, `AGPL-3`, `Apache-2.0`, `MPL-2.0`, `None`.                                                    |
-| `ghcVersions`    | [GHC]   | `summoner` uses default `GHC-9.12.3`. However, additionally you can specify other versions. For each version `x.y.z` the `stack-x.y.z.yaml` will be created. Use `summon show ghc` to see all supported GHC versions. |
+| `ghcVersions`    | [GHC]   | `summoner` uses default `GHC-9.12.2`. However, additionally you can specify other versions. For each version `x.y.z` the `stack-x.y.z.yaml` will be created. Use `summon show ghc` to see all supported GHC versions. |
 | `github`         | Bool    | Turn on `GitHub` integration by default?                                                                                                                             |
 | `gitignore`      | [Text]  | List of files you want added to the default `.gitignore`. (Ignored if `github = false`)                                                                              |
 | `noUpload`       | Bool    | Do not upload to GitHub, but create all GitHub related files if specified (Ignored if `github = false`)                                                              |

summoner-cli/examples/cabal-full/.github/workflows/ci.yml

@@ -28,7 +28,7 @@ jobs:
           - "9.6.7"
           - "9.8.4"
           - "9.10.3"
-          - "9.12.3"
+          - "9.12.2"
         exclude:
           - os: macOS-latest
             ghc: 9.10.3

summoner-cli/examples/cabal-full/.travis.yml

@@ -21,7 +21,7 @@ jobs:
   - ghc: 9.6.7
   - ghc: 9.8.4
   - ghc: 9.10.3
-  - ghc: 9.12.3
+  - ghc: 9.12.2
 
 install:
   # HLint check

summoner-cli/examples/cabal-full/appveyor.yml

@@ -21,12 +21,12 @@ environment:
     CABOPTS: --store-dir=C:\\SR
 
   matrix:
-    - GHCVER: 9.12.3
+    - GHCVER: 9.12.2
 
 install:
   - choco source add -n mistuke -s https://www.myget.org/F/mistuke/api/v2
   - choco install -y cabal --version 3.6.2.0
-  - choco install -y ghc   --version 9.12.3
+  - choco install -y ghc   --version 9.12.2
   - refreshenv
 
 before_build:

summoner-cli/examples/cabal-full/cabal-full.cabal

@@ -26,7 +26,7 @@ tested-with:         GHC == 8.4.4
                      GHC == 9.6.7
                      GHC == 9.8.4
                      GHC == 9.10.3
-                     GHC == 9.12.3
+                     GHC == 9.12.2
 
 source-repository head
   type:                git

summoner-cli/examples/cabal-minimal/cabal-minimal.cabal

@@ -12,10 +12,10 @@ copyright:           2022 Kowainik
 build-type:          Simple
 extra-doc-files:     README.md
                      CHANGELOG.md
-tested-with:         GHC == 9.12.3
+tested-with:         GHC == 9.12.2
 
 common common-options
-  build-depends:       base ^>= 4.21.1.0
+  build-depends:       base ^>= 4.21.0.0
 
   ghc-options:         -Wall
                        -Wcompat

summoner-cli/examples/cabalScript.hs

@@ -1,7 +1,7 @@
 #!/usr/bin/env cabal
 {- cabal:
 build-depends:
-  , base ^>= 4.21.1.0
+  , base ^>= 4.21.0.0
 -}
 
 main :: IO ()

summoner-cli/examples/full-batteries/.github/workflows/ci.yml

@@ -30,7 +30,7 @@ jobs:
           - "9.6.7"
           - "9.8.4"
           - "9.10.3"
-          - "9.12.3"
+          - "9.12.2"
         exclude:
           - os: macOS-latest
             ghc: 9.10.3
@@ -141,7 +141,7 @@ jobs:
           - "9.6.7"
           - "9.8.4"
           - "9.10.3"
-          - "9.12.3"
+          - "9.12.2"
 
     steps:
     - uses: actions/checkout@v4