Compilation error using MicroHS (main.c eval.c)

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1

I’ve dipped my toes into MicroHs and I’m running into a compilation error when I try to invoke it from an external directory. The Haskell code is simply the default hello world from a cabal init

 ( ../MicroHs/bin/mhs
 -i../MicroHs/lib
 -I../MicroHs/src/runtime
 -I../MicroHs/src/runtime/unix
 -I../MicroHs/src
  app/Main.hs -o out )
cc1: fatal error: ./src/runtime/main.c: No such file or directory
compilation terminated.
cc1: fatal error: ./src/runtime/eval.c: No such file or directory
compilation terminated.

/home/deepak/code/haskell/mhsb/../MicroHs/bin/mhs: uncaught exception: error: command failed: cc  -I./src/runtime -I./src/runtime/unix  -D__MHS__ '-I../MicroHs/src/runtime' '-I../MicroHs/src/runtime/unix' '-I../MicroHs/src'  ./src/runtime/main.c ./src/runtime/eval.c /tmp/mhsc6idpMa.c  -oout

It seems that mhs is still trying to find main.c and eval.c in the current directory, and -I../MicroHs/src does not seem to be the right flag to pass to resolve those files elsewhere. I can get it to work by symlinking or running from the MicroHs directory, but my hope was to get it working with guix

2 Likes
2

The solution here was to set MHSDIR

 with-env { MHSDIR:"../MicroHs" } { ( ../MicroHs/bin/mhs
  app/Main.hs -o out ) }
:  ./out
Hello, Haskell!
3

Did you do make install?

All you should have to do is to extend your PATH so it can find the installed mhs and it should just work.

1 Like
4

I didn’t do a make install in this case because I will be creating a guix derivation that will put the package into the store (GNU alternative to nix https://guix.gnu.org/en/blog/2021/building-derivations-how-complicated-can-it-be/ )