I have some questions about linking c code against fortran libraries.
Suppose I have a code foo.c which calls routines in a fortran library libfortlib.
First question: is g77 foo.o -lfortlib equivalent to gcc foo.o -lfortlib -lfrtbegin -lg2c -lm -shared-libgcc
or does it actually matter that the compiler was invoked as g77.
At any rate, neither of these is successful and give equivalent error:
gcc-3.2.1/i686-pc-linux-gnu/libf2c/libF77/main.c: undefined reference to `MAIN__'
It was my understanding that linking with g77 was supposed to tie up the stuff so that the entry point into the executable was somewhere in libfrtbegin which then called foo.o:main() after libg2c initialization. The library is a debian build (OK, I might as well be specific -- it's lapack) but the behavior doesn't seem to depend on whether I compile and link with any of the debian build gcc's (2.95, 3.0, 3.0.4) or a handbuilt 3.2.1.
If no one has the magic solution for me, what might be even better is if someone at least has some pointers to discussions where these issues are raised (other than (e.g.): http://gcc.gnu.org/onlinedocs/gcc-3.3.2/g77/Startup-Code.html#Startup%20Code )
at a level accessible to physicists ;)
Cheers, Craig
