Re[2]: [Haskell-cafe] FFI, C/C++ and undefined references
Hello Daniel, Thursday, January 14, 2010, 11:08:24 PM, you wrote: i think you are wrong. stdcall used for std windows dlls, but gcc by default generates ccall things. and cl anyway useless here Just an idea. Are you on windows? If so, then your foreign calls would probably have to be foreign import stdcall srilm.h whatever ... instead of foreign import ccall ... Malcolm Wallace wrote: However, if you are unsure of which Haskell packages are needed, it is wise to let ghc work out the dependencies for you, e.g. with ghc --make Main.hs slirm.o It cannot work out the C/C++ dependencies though, so every time you get undefined reference linking errors, you must discover which C code provides those symbols, and add its object file to the commandline by hand. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Best regards, Bulatmailto:bulat.zigans...@gmail.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] FFI, C/C++ and undefined references
Hello DNM, Thursday, January 14, 2010, 10:42:42 PM, you wrote: there is better way rather than playing with random bits. just find tutorial on FFI, and try it. once this example works, start modifying it to learn various aspects of ffi and add functionality you need it's one thing i've learned in those 20 years - go forward in small steps keeping working code instead of jumping at large distance and then spending days without any clue Which is weird, because 'srilm.o'/'srilm.h' are the files that define the mysterious undefined references. I'll keep plugging away and report back when (or whether) I make some progress. In the meanwhile, if anyone has a clue, I'm all ears. Best, D.N. Malcolm Wallace wrote: However, if you are unsure of which Haskell packages are needed, it is wise to let ghc work out the dependencies for you, e.g. with ghc --make Main.hs slirm.o It cannot work out the C/C++ dependencies though, so every time you get undefined reference linking errors, you must discover which C code provides those symbols, and add its object file to the commandline by hand. -- Best regards, Bulatmailto:bulat.zigans...@gmail.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Re[2]: [Haskell-cafe] FFI, C/C++ and undefined references
2010/1/14 Bulat Ziganshin bulat.zigans...@gmail.com: there is better way rather than playing with random bits. just find tutorial on FFI, and try it. once this example works, start modifying it to learn various aspects of ffi and add functionality you need Also binding to a C library is easier than binding to a C++ one, if you can think of another library rather than SRILM that will meet your needs... Best wishes Stephen ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] FFI, C/C++ and undefined references
Hello DNM, Thursday, January 14, 2010, 7:07:43 AM, you wrote: Yes, I thought of doing this, but then thought it was better to use a so-called managed foreign pointer via newForeignPtr. i recommend to use Ptr and switch to ForeignPtr only when you will study how to use it. overall, unsafe* functions are really unsafe, and using them without learning will lead to mysterious problems. it's like painting with eyes closed Good point. I would do this if I planned to train or update the language model from within Haskell, but, as it stands, I just want to train it once (at the command line, using the built-in mechanisms of SRILM) and then read in the ARPA-formatted language model file for use in Haskell. you may add problems by using unsafePerformIO. i recommend you to learn first how to manage FFI without it, make program work, and only then try to use it. eat elephant in small pieces! look into http://haskell.org/haskellwiki/IO_inside -- Best regards, Bulatmailto:bulat.zigans...@gmail.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re[2]: [Haskell-cafe] FFI, C/C++ and undefined references
Hello Brandon,
Thursday, January 14, 2010, 7:40:45 AM, you wrote:
Really, the only reason in this case is that there is no equivalent
for `extern C' that you can apply to a function definition, only to
a declaration
it works with GCC:
extern C int c_szOpenArchive (TABI_ELEMENT* params)
{
}
--
Best regards,
Bulatmailto:bulat.zigans...@gmail.com
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