SevenThunders wrote:
I have a large Haskell/C project that needs to be linked against an even larger set of C libraries and object files (OpNet) on a linux box (Fedora Core 7). So far I have been able to link my Haskell libraries to some C test code containing a main function without incident. However the link flags are very complex having been extracted from ghc. (e.g. it requires a host of -u flags and then a bunch of links to external C libraries including a long list of Haskell libraries.)
Unfortunately control over the OpNet compilation and linking process is weak at best. Moreover it is not clear how the linking occurs and there is some suspicion that it ultimately creates a dynamic link library which it loads from some external process (the exact calls to gcc are hidden). During the OpNet build we get the following error
/usr/lib/ghc-6.6.1/libHSrts.a(Main.o): In function `main': Main.c:(.text+0x22): undefined reference to `__stginit_ZCMain' Main.c:(.text+0x43): undefined reference to `ZCMain_main_closure' collect2: ld returned 1 exit status
I do not get this error when statically linking my libraries to a standalone C function containing a main() function. What should I look for? Are there known work arounds to this problem? It's troubling that exporting Haskell to C should be this problematic. Unfortunately I can not use ghc to compile the OpNet code as you might imagine.
Does this error occur because of dynamic linking? That is if this were all packed into some library without a main function in C it would try to link to the Main.o object file in libHSrts.a, which has some unsatisfied links since there is no main function in the Haskell code. So does static linking always fix this? Is it possible to fix it by providing a dummy main function in a dynamic link library? I don't know if the latter is possible in linux. -- View this message in context: http://www.nabble.com/GHC-linking-problems-tf4270650.html#a12171221 Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.