#13093: Runtime linker chokes on LLVM function on Windows -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Runtime | Version: 8.0.1 System (Linker) | Keywords: | Operating System: Windows Architecture: | Type of failure: GHCi crash Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This error prevents the [http://hackage.haskell.org/package/llvm-general llvm-general] library from loading in GHCi on Windows. I don't know how to reproduce this error without using LLVM. First, you need to install LLVM. On Windows, you can install it with MSYS2: {{{ pacman -S mingw-w64-x86_64-llvm }}} Currently, this gives you LLVM-3.9, although I've reproduced it with LLVM-3.8 as well. Now define this Haskell file: {{{#!hs module Main (main) where import Foreign.C.Types newtype LLVMBool = LLVMBool CUInt deriving Show foreign import ccall unsafe "LLVMIsMultithreaded" isMultithreaded :: IO LLVMBool main :: IO () main = isMultithreaded >>= print }}} If you compile it, it works OK: {{{ $ ghc LLVM.hs -fforce-recomp $(llvm-config --libs) $(llvm-config --system- libs) -lstdc++-6 -lgcc_s_seh-1 [1 of 1] Compiling Main ( LLVM.hs, LLVM.o ) Linking LLVM.exe ... $ ./LLVM LLVMBool 1 }}} Or, if you're allergic to `llvm-config`: {{{ $ ghc LLVM.hs -fforce-recomp -lLLVMLTO -lLLVMObjCARCOpts -lLLVMSymbolize -lLLVMDebugInfoPDB -lLLVMDebugInfoDWARF -lLLVMGlobalISel -lLLVMCoverage -lLLVMTableGen -lLLVMLineEditor -lLLVMOrcJIT -lLLVMMIRParser -lLLVMARMDisassembler -lLLVMARMCodeGen -lLLVMARMAsmParser -lLLVMARMDesc -lLLVMARMInfo -lLLVMARMAsmPrinter -lLLVMObjectYAML -lLLVMLibDriver -lLLVMOption -lLLVMX86Disassembler -lLLVMX86AsmParser -lLLVMX86CodeGen -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMDebugInfoCodeView -lLLVMX86Desc -lLLVMMCDisassembler -lLLVMX86Info -lLLVMX86AsmPrinter -lLLVMX86Utils -lLLVMMCJIT -lLLVMPasses -lLLVMipo -lLLVMVectorize -lLLVMLinker -lLLVMIRReader -lLLVMAsmParser -lLLVMInterpreter -lLLVMExecutionEngine -lLLVMRuntimeDyld -lLLVMObject -lLLVMMCParser -lLLVMCodeGen -lLLVMTarget -lLLVMScalarOpts -lLLVMInstCombine -lLLVMInstrumentation -lLLVMTransformUtils -lLLVMMC -lLLVMBitWriter -lLLVMBitReader -lLLVMAnalysis -lLLVMProfileData -lLLVMCore -lLLVMSupport -lpsapi -lshell32 -lole32 -luuid -lstdc++-6 -lgcc_s_seh-1 [1 of 1] Compiling Main ( LLVM.hs, LLVM.o ) Linking LLVM.exe ... $ ./LLVM LLVMBool 1 }}} If you load it into GHCi, however, things go awry: {{{ $ ghci $(llvm-config --libs) $(llvm-config --system-libs) -lgcc_s_seh-1 GHCi, version 8.0.2: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from C:\Users\RyanGlScott\AppData\Roaming\ghc\ghci.conf Ok, modules loaded: Main (LLVM.o).
main ghc.exe: LLVM.o: unknown symbol `LLVMIsMultithreaded' }}}
On GHC 8.0.1 and HEAD, it's a slightly different error: {{{
main
ByteCodeLink: can't find label During interactive linking, GHCi couldn't find the following symbol: LLVMIsMultithreaded This may be due to you not asking GHCi to load extra object files, archives or DLLs needed by your current session. Restart GHCi, specifying the missing library using the -L/path/to/object/dir and -lmissinglibname flags, or simply by naming the relevant files on the GHCi command line. Alternatively, this link failure might indicate a bug in GHCi. If you suspect the latter, please send a bug report to: glasgow-haskell-bugs@haskell.org }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13093 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler