## Summary Compared to GHC 9.12.3 and earlier, GHCi 9.14.1 breaks the `:add` command. This, consequently, affects `stack ghci` and may possibly have adverse implications for HLS support for people who build with Stack. ## Steps to reproduce With GHC 9.12.3 on Ubuntu 24.04.1 LTS (via WSL 2) and a 'toy' package (see further below), all is as expected: ~~~text $ stack ghc -- --interactive -i/home/mpilgrem/code/Haskell/testGhc9123/src GHCi, version 9.12.3: https://www.haskell.org/ghc/ :? for help ghci> :add Lib [1 of 1] Compiling Lib ( /home/mpilgrem/code/Haskell/testGhc9123/src/Lib.hs, interpreted ) Ok, one module added. ghci> :! ls /home/mpilgrem/code/Haskell/testGhc9123/src Lib.hs ghci> ~~~ However, the direct equivalent with GHC 9.14.1 is as follows (and GHC cannot now find the `Lib` module): ~~~text $ stack ghc -- --interactive -i/home/mpilgrem/code/Haskell/testGhc9141/src GHCi, version 9.14.1: https://www.haskell.org/ghc/ :? for help ghci> :add Lib <interactive>: error: [GHCi-23305] Module Lib not found Ok, no modules added. ghci> :! ls /home/mpilgrem/code/Haskell/testGhc9141/src Lib.hs ghci> ~~~ In both cases, the toy package is a simple one (created using, say, `stack --snapshot ghc-9.14.1 new testGhc9141`) with a `Lib` module in `Lib.hs` in the location indicated above by the `ls` command. (`stack ghc` just executes `ghc` with the arguments following `--`.) The same changed behaviour occurs on Windows. ## Expected behavior Either (a) that GHCi 9.14.1 behaves the same way as GHC 9.12.3 and earlier, in this regard; or (b) that the reason for GHCi 9.14.1's changed behaviour is documented in the GHC User's Guide. ## Environment * GHC version used: 9.14.1 (bug) 9.12.3 (working) Optional: * Operating System: Ubuntu 24.04.1 LTS (via WSL 2), or Microsoft Windows [Version 10.0.26200.7623] * System Architecture: x86_64