Hi, Suddenly started getting the following linker error after I moved code around in my project. It only seems to occur when I am building one specific cabal test target. When building a dependent build it build successfully but cabal repl test-xxx fails. I have no consistent way to repro but I will keep trying and file a defect.. GHCi, version 8.8.4: https://www.haskell.org/ghc/ :? for help GHC runtime linker: fatal error: I found a duplicate definition for symbol __gmpn_sec_sqr_itch whilst processing object file C:\Users\sumit\Apps\ghc-8.8.4\mingw\lib\libgmp.dll.a The symbol was previously defined in C:\Users\sumit\Apps\ghc-8.8.4\lib\integer-gmp-1.0.2.0\HSinteger-gmp-1.0.2.0.o This could be caused by: * Loading two different object files which export the same symbol * Specifying the same object file twice on the GHCi command line * An incorrect `package.conf' entry, causing some object to be loaded twice. ghc.exe: panic! (the 'impossible' happened) (GHC version 8.8.4 for x86_64-unknown-mingw32): loadArchive "C:\\Users\\sumit\\Apps\\ghc-8.8.4\\mingw\\lib\\libgmp.dll.a": failed Please report this as a GHC bug: https://www.haskell.org/ghc/reportabug CallStack (from HasCallStack): die', called at .\\Distribution\\Client\\ProjectOrchestration.hs:1041:55 in main:Distribution.Client.ProjectOrchestration cabal.exe: repl failed for mkr-txn-0.1.0.0-inplace-test-mkr-txn. Regards Sumit