That statement means that you can create a separate library, which can be called from a C program.

Doing what you want is to include pascal object files directly in a C program. That is only possible if you create your own loader stub.

Michael.

Hi again,

I still don't succeed in linking Free Pascal compiled code with a C program.

When linking with the shared library built by fpc, I have problems with undefined symbols, which are defined in the loaders.

$ gcc -o test_shared test2.o -L. -lsoTest3
./libsoTest3.so: undefined reference to `__stkptr' ./libsoTest3.so: undefined reference to `_haltproc' ./libsoTest3.so: undefined reference to `operatingsystem_parameter_argc' ./libsoTest3.so: undefined reference to `operatingsystem_parameter_argv' collect2: ld returned 1 exit status

When linking in the loader prt0.o too, there are symbol conflicts with /usr/lib/crt1.o (_start, __data_start) if I call ld through gcc.

$ gcc -o test_shared test2.o prt0.o -L. -lsoTest3
prt0.o: In function `_start':
(.text+0x0): multiple definition of `_start'
/usr/lib/gcc/x86_64-linux-gnu/4.0.3/../../../../lib64/crt1.o:../sysdeps/x86_64/elf/start.S:65: first defined here prt0.o: In function `data_start':
(.data+0x0): multiple definition of `__data_start' /usr/lib/gcc/x86_64-linux-gnu/4.0.3/../../../../lib64/crt1.o:(.data+0x0): first defined here collect2: ld returned 1 exit status

Exactly the same happens when linking statically.

If I call ld directly, linking succeeds, but the main() of the C program never gets called...

However, according to the FPC Programmer's Guide, "using a pascal library from a C program" (12.4) seems to be supported...

Do I miss something ?

Thx for your help,

Dominique Leducq

That is actually what I want to do. How can I achieve this ? I followed the steps in the Programmer Guide, to no avail.

Doing what you want is to include pascal object files directly in a C program. That is only possible if you create your own loader stub. Michael.

Add a call to FPC_INITIALIZEUNITS before calling any FPC routines, and it should work fine.

Michael.

OK, I've done it with this little trick :

$ gcc -c test3.c
$ gcc -o test3 test3.o dummy.o -L. -lsoTest5

with the source of dummy.c:

#define NULL (void *)0

long operatingsystem_parameter_argc = 0;
char **operatingsystem_parameter_argv = NULL;
char **operatingsystem_parameter_envp = NULL;
void *__stkptr = NULL;

void _haltproc(long e)
{

  return;

}

When calling a library function that do no IO (only arithmetics on the parameters), it works. When doing simple IO (writeLn), it doesn't: I see calls to handleerror_frame, get_frame, get_caller_frame, get_caller_addr, break_error... when debugging, following calls to write_text_pchar_as_array and IOcheck

Dominique Leducq.

It works, thanks !

Dominique.