#12209: Windows: ByteCodeLink can't find labels "lseek" and "write" -------------------------------------+------------------------------------- Reporter: thomie | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Runtime System | Version: 8.0.1 (Linker) | Resolution: | Keywords: Operating System: Windows | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Phyx-): `lseek` and `write` existed before Microsoft deprecated the POSIX functions. As such, they did used to exist https://msdn.microsoft.com/en- us/library/ms235323.aspx During `WAY=ghci` we query `msvcrt.dll` directly which is the C runtime. The function has been deprecated long enough that it's been removed. {{{ e:\temp\dynamic>dumpbin /exports c:\Windows\System32\msvcrt.dll | findstr lseek 496 1EF 0001D080 _lseek = _lseek 497 1F0 0001D230 _lseeki64 = _lseeki64 e:\temp\dynamic>dumpbin /exports c:\Windows\System32\msvcrt.dll | findstr write 998 3E5 0001FA20 _write = _write 1113 458 0004DB90 fwrite = fwrite }}} During linking, `Mingw-w64` ends up linking against the import library `msvcrt.a` which contains a redirect from `lseek` to `_lseek`. Probably for backwards compatibility. {{{ $ nm -s "inplace\mingw\x86_64-w64-mingw32\lib\libmsvcrt.a" | grep lseek _lseeki64 in dcnfs00450.o __imp__lseeki64 in dcnfs00450.o _lseek in dcnfs00449.o __imp__lseek in dcnfs00449.o lseek in dcnfs00448.o __imp_lseek in dcnfs00448.o 0000000000000000 I __imp__lseeki64 0000000000000000 T _lseeki64 0000000000000000 I __imp__lseek 0000000000000000 T _lseek 0000000000000000 I __imp_lseek 0000000000000000 T lseek }}} So the correct solution would be to use the `_` versions. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12209#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler