Bad interface file on repeated rebuilds

[ekmett]

When I alternate between

cabal v2-repl --repl-options=-fobject-code --repl-options=-v1 --repl-options=-ferror-spans    --repl-options=-j

and

cabal v2-test

in my current project several times, eventually I get something like:

test/Spec.hs:5:1: error:
    Bad interface file: /Users/ekmett/codex/dist-newstyle/build/x86_64-osx/ghc-8.6.4/harfbuzz-0/build/Graphics/Harfbuzz.hi
        mismatched interface file ways (wanted "", got "dyn")
  |

The only way I've been able to fix it is to go in and nuke that sub-directory and rebuild.

Guessing we have some bad logic about dynamic vs. static libraries somewhere?

To be fair the project itself uses template-haskell internally to build up stuff for FFI, so that may somehow be a factor, but I'm not sure how to distill a minimal test case.

[robrix]

I’ve had the same problem, and have for the time being worked around it using --builddir to use a separate dist directory for the REPL.

[fgaz]

I'm experiencing a similar error when enabling program-default-options ghc-options: -dynamic, but on a store package:

cabal build cabal-tests
Build profile: -w ghc-8.8.4 -O1
In order, the following will be built (use -v for more details):
 - cabal-testsuite-3 (exe:cabal-tests) (first run)
[1 of 1] Compiling Main             ( /home/fgaz/cabal/dist-newstyle/build/x86_64-linux/ghc-8.8.4/cabal-testsuite-3/setup/setup.hs, /home/fgaz/cabal/dist-newstyle/build/x86_64-linux/ghc-8.8.4/cabal-testsuite-3/setup/Main.o )

/home/fgaz/cabal/dist-newstyle/build/x86_64-linux/ghc-8.8.4/cabal-testsuite-3/setup/setup.hs:4:1: error:
    Bad interface file: /home/fgaz/.cabal/store/ghc-8.8.4/Cabal-3.2.1.0-3867a82217cd835cc6bce9e5c630fa4fdaf4e06482844b349cee070982f81548/lib/Distribution/Backpack.hi
        mismatched interface file ways (wanted "", got "dyn")
  |
4 | import Distribution.Backpack
[...]