Hi,
thank for all the help,
I do not know what I have done but I have a new error:
C:/freesw/lib/sndfile-1.lib: error adding symbols: File in wrong format
collect2.exe: error: ld returned 1 exit status
src\CMakeFiles\libfluidsynth.dir\build.make:151: recipe for target 'src/libfluidsynth-2.dll' failed
mingw32-make.exe[2]: *** [src/libfluidsynth-2.dll] Error 1
CMakeFiles\Makefile2:95: recipe for target 'src/CMakeFiles/libfluidsynth.dir/all' failed
mingw32-make.exe[1]: *** [src/CMakeFiles/libfluidsynth.dir/all] Error 2
Makefile:150: recipe for target 'all' failed
mingw32-make.exe: *** [all] Error 2