If we look at the source code for hscCompileCore, it would seem that it creates a ModGuts with mkModGuts which has an empty mg_exports, which means that in all cases there will be no exported items. So it's not very useful! You should file a bug. We should fix this, but in the mean time, you could simply copypaste the definition of hscCompileCore, and modify it so that you do set up the ModGuts correctly with a real mg_exports field. Edward Excerpts from Marek Wawrzos's message of 2015-10-08 07:22:01 -0700:
Hello,
I'm trying to compile some module with GHC API. I'm going to feed GHC with Core generated by me.
So far is noticed, that function compileCoreToObj ends with an runtime error on each call. In spide of this function produces some *.o and *.hi files. However, produced interface file does not contain any item in exports field, what makes compiled module unusable.
Because of this problem, I tried to achieve my goal by using steps described here: https://wiki.haskell.org/GHC/As_a_library (the second example) I was able to print out Core produced form file. If I'm not wrong, modifying structures passing on between sequent calls does not effect on produced *.hi and *.o files. Both files are generated by `load LoadAllTargets' call, and further calls (parseModule, loadModule, ...) does not effect on generated files.
Could You give me any advices in that topic? Am I right about compileCoreToObj and functions mentioned above?
Best Regards, Marek