I downloaded your project and made it compile.
1- add ALL files to your solution (*.c and *.h files). Your solution only contains one .c file...
2-
inline
keyword cannot be used in *.c files with Visual Studio. So rename all your *.c files into *.cpp files.
3- edit the
m4ri.h
file and comment the
__cplusplus
block out.
#include "permutation.h"
#include "packedmatrix.h"
#include "brilliantrussian.h"
#include "strassen.h"
#include "grayflex.h"
#include "parity.h"
#include "trsm.h"
#include "pls.h"
#include "pls_mmpf.h"
#include "solve.h"
#include "echelonform.h"