External C dll

[Strombolio]

Hi, I'm experimenting and trying to make a collision manager dll, following these two pages
http://www.mingw.org/wiki/sampleDLL
http://www.troubleshooters.com/codecorn ... alls_c.htm

But when I try to require the library from Love, it gives me this

error loading module 'test' from file '.\test.dll':
%1 is not a valid Win32 application.

I also tried ffi, but it just gave me a nil
I'm baffled and don't know where to go next, please help?

[slime]

Be sure to build it for the same architecture as your copy of LÖVE - i.e. make a 32 bit build if you're running 32 bit love, or a 64 bit build if you're running 64 bit love.

[giantofbabil]

I'm pretty new to Love2D and programming in general but what is the advantage of a .dll over another .lua file to manage something?

[bobbyjones]

C code could potentially be faster or flexible. But there is more disadvantages than advantages. Better off using ffi if you want to use c to boost the performance

[Strombolio]

Be sure to build it for the same architecture as your copy of LÖVE - i.e. make a 32 bit build if you're running 32 bit love, or a 64 bit build if you're running 64 bit love.

Aw, I always forget about that!

Now ffi gives me
missing declaration for symbol 'test'

and require gives me
error loading module 'test' from file '.\test.dll':
The specified procedure could not be found.

But I think I did it right
int __declspec(dllexport) test(int num){
return num+5;
}

gcc -shared -o test.dll test.c -Wl,--out-implib,test.a

and I also tried
gcc test.c -shared -o test.dll -Wl,--no-undefined,--enable-runtime-pseudo-reloc

and I also tried adding __stdcall to the function, but I don't really know what that does

[airstruck]

Now ffi gives me
missing declaration for symbol 'test'

I don't see any Lua code here so I'll just go out on a limb and guess that the error's exactly what it looks like and the symbol was never declared (something like ffi.cdef 'int test (int);').

This is covered at the very beginning of the documentation for the ffi api.