Static libraries containing routines with identical names

Hi,

I have a problem concerning the names of routines contained in static libraries.

In fact, I have hundreds of libraries written in Fortran, that I need to interface in a unique C program (and I have no way to regenerate these libraries...). The main problem is that all these libraries contain routines with identical names. I really do not know how to make it correctly...

Thanks in advance for your help,

Best,
CCox

Which compiler are you using?

I suppose you could link each library with thin wrapper functions (with unique names), then strip all the symbols which would otherwise clash.

Hi,

Thanks for your reply. I'm using gcc 4.X, but I'm not sure to understand what you propose...

Thanks,
CCox

Let's say one of your libraries contains a function called foo().

Then create a simple wrapper function which just calls foo, say

Code:

---

// wrap_foo.c
int wrap_foo ( int a, double b ) {
  return foo ( a, b );
}

---

Start with say
ar x libfoo.a
To extract all the individual object files from the library.

Then you would do something like
gcc -c wrap_foo.c
echo wrap_foo > keepsyms.txt
ld -r -o wrapped_foo.o --retain-symbols-file keepsyms.txt wrap_foo.o foo.o
Which
- compiles the wrapper
- links the wrapper to the existing function, and removes the unwanted symbols.

You can then add the new objects back into a library you can link against.

If the library functions have the same names, I'm guessing they have the same interfaces as well? This could give you some scope with automating this task.

http://sourceware.org/binutils/docs-...s.html#Options

Many thanks, I will have a try, and also find a way to automate the process.

Cheers,
CCox

Hi,

In fact, the fortran libs I want to interface with C contain something like hundreds of .o, containing procedures with identical names for all the libraries.

Even if I understand the principle with one file, I am not sure what to do with all my files.
Do you think there is a way to assemble all the fortran .o of one library in a single .o, and to perform then the operation you propose?

Thanks a lot,
Best,
CCox

So long as the symbols are unique while you're doing it, yes.

A single wrap.c file for all the Fortran .o files in a single library would work.

The only downside would be it would not be a library as such, so you'd get all the code linked even if you only wanted part of it. But if you're linking with all of it, there isn't a lot of difference.

If you do
file fortran.o

file is a command which tells you what type of file it is. It should print out something like
ELF object, not stripped
or something like it.

An alternative might be to write an ELF manipulation program (the file format is documented in various places, and IIRC a few libraries to make it easy to do) which simply renames symbols "in situ". But I've no idea how involved that would be, but the end result would be very quick :)

OK, thank you, I will think about all this...

Cheers,
CCox