Take a look at the libcspline3.dll in Dependency Walker. You're likely missing a libgomp dll which you'll need to copy from your compiler installation and put it next to libcspline3.dll. Where did you install the gcc compiler from and are you calling it from inside an environment like cygwin or msys[2]?
On Tuesday, January 19, 2016 at 4:15:45 PM UTC-8, [email protected] wrote: > > > > Hi, > > > I am trying to call C code from Julia.It works for 'regular' C code but > now I have code that (potentially) uses OpenMP which causes trouble. I am > trying to interpolate a function using a spline approximation. In short, if > I type: > > gcc -shared -O3 nspline_omp.c -o libcspline.dll -ffast-math > > > and then call one of the functions in the library from Julia using ccall, > it works. But judging from the speed and comparison with other languages, > only 1 thread is used. The code certainly supports multi-threading, for a > my friend of mine on his Mac, it worked. If I type: > > gcc -shared -O3 nspline_omp.c -o libcspline2.dll -ffast-math -fopenmp > > iand try to call it from Julia, it doesn't work anymore, in particular: > > LoadError: error compiling spline: could not load library "libcspline2.dll" > The specified module could not be found. > > > Libdl.dlopen("libcspline2.dll") > > gives the same error. As an example, consider: > > #include<omp.h> > > int banana(int hello) { > int nt; > #pragma omp parallel > { > nt = omp_get_num_threads(); > } > return nt; > } > > > #include <stdio.h> > int main() { printf("%d\n", banana(12)); } > > > which perfectly works when compiled as .exe (gcc helloworld.c -fopenmp). When > I try to compile > > #include <stdlib.h> > #include <omp.h> > > int banana(int hello) { > int nt; > #pragma omp parallel > { > nt = omp_get_num_threads(); > } > return nt; > } > > as a shared library using > > gcc -shared -O3 helloworld2.c -o libcpsline3.dll -ffast-math -fopenmp > > and then in Julia: > > Libdl.dlopen("libcspline3.dll") > LoadError: could not load library "libcspline3.dll" > The specified module could not be found. > > > Finally, I am new to Julia and C and basically I have not much of an idea > what I am doing, so it could be an obvious mistake. Thanks for your help. > > > >
