On Mon, 16 Oct 2017 09:20:26 +0300 Gleb Popov <[email protected]> wrote: > I'm porting an application (DLib, https://reviews.freebsd.org/D12559) that > uses BLAS and LAPACK, and I have some questions. > > 1. Is there any pure C implementation that does not require Fortran > compiler?
Probably not, BLAS and LAPACK are Fortran libraries. Any implementation in C still provides Fortran wrappers. And often these implementations only implement performance critical functions and use the original Fortran for everything else. > 2. My application looks for cblas_ddot function in BLAS library, but the > default library (netlib) doesn't seem to have that. It has ddot, though, so > I'm not sure if it is a wrong check on app's side, or netlib is indeed > doesn't suit there. For now I've used openblas, but I'm also not sure if it > is a right choice. It's part of CBLAS which is also included in OpenBLAS. > 3. How to link properly to any of BLAS libraries? All BLAS implementations > blaslapack.mk features require Fortran. This implies USE_GCC=yes, so these > are compiled with GCC, not Clang. Now when I try to link Clang-compiled > DLib to GCC-compiled openblas, I get undefined references: > > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__getf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__floatunditf@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__subtf3@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__multf3@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__unordtf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__lttf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__addtf3@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__gttf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__divtf3@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__letf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__netf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__floatditf@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__eqtf2@GCC_4.6.0' > //usr/local/lib/gcc6/libgfortran.so.3: undefined reference to > `__floatsitf@GCC_4.6.0' > > I've tracked these symbols to /usr/local/lib/gcc6/libgcc_s.so. But there is > also /usr/lib/libgcc_s.so and it doesn't have such symbols. I suspect this > is the source of the error, but I wasn't able to fix it. Passing -Wl,-rpath > as advised by lang/gcc6 pkg-message doesn't help. The only workaround I > came up with is USE_GCC=yes to compile DLib itself, but that's pretty > unsatisfactory. This is a known problem. If your port depends on another port that has USES=fortran the easiest is to add USES=fortran to your port as well. C code will still be built with Clang then. _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-ports To unsubscribe, send any mail to "[email protected]"
