[Haskell-cafe] Re: FFI and LD_PRELOAD -> segfault

[Stephan Walter]

On Sun, 24 Sep 2006 20:20:55 +0300, Anatoly Zaretsky wrote:

> #include <HsFFI.h>
> 
> extern void __stginit_Socks(void);
> 
> static void __attribute__ ((constructor)) my_init(void) {
>   int argc = 1;
>   char *argv[] = {"Haskell shared object"};
>   char **argvp = argv;
>   hs_init(&argc, &argvp);
>   hs_add_root(__stginit_Socks);
> }
> 
> static void __attribute__ ((destructor)) my_fini(void) {
>   hs_exit();
> }

That solved it! If anyone wants to do the same: I put the code you gave
above in hsinit.c, and compiled everything with:

  ghc -Wall -c -fffi testffi.hs
  gcc -g -Wall -I/usr/lib/ghc-6.4.2/include -c -o hsinit.o hsinit.c
  ghc -Wall -optl "-shared" -o libtestffi.so \
    hsinit.o testffi.o testffi_stub.o

Then, using LD_PRELOAD with the test program worked fine.

Thanks a lot!

-Stephan