I have installed OpenBlas in TX1 and the time_dgemm example compiles fine with the gcc. However, I need to be able to link the rest of my code with OpenBlas using g++. When I try to compile the time_dgemm example with g++ it fails, giving the linking error "...undefined reference to 'dgemm_(......". The only change is using the g++ instead of gcc.
I have tried to compile the OpenBLAS library with g++ (make CC=g++), as other people suggested in the past, but the compilation fails when it tries to compile some part of BLAS.
Any ideas?
If some people have the same issue, I was able to compile with the following command:
g++ openBlasExample.cpp -I /usr/include/openblas -lopenblas
You can find your openblas include folder by using on Linux:
locate openblas
More info here:
https://gist.github.com/xianyi/6930656
Related
I was creating program on windows with SDL2 and the program worked fine, but when I changed my os to linux mint (and install code::blocks, gcc, g++, SDL2), I run into troubles with compiling my code.
I have one error:
- ld||cannot find -lmingw32|
I guess that I don't have mingw32 library, where can I get it? Or is the problem diferent?
BTW: I also tryed to google it.
Thank for response.
Read the manual.
On linux you don't need -lmingw32. Instead, use
`sdl2-config --libs`
to get the list of all needed linker flags.
Example usage:
gcc -o myprogram myprogram.o `sdl2-config --libs`
Problem was solved by removing linker on mingw32 and lib rotozoom.h.
I have a fresh install of OS X 10.11.4 that I immediately installed the Xcode toolchain on, then Homebrew, then Boost 1.60. In order to test that everything had gone well, I wrote the following code on my Desktop.
#include <iostream>
#include <boost/filesystem.hpp>
int main() {
boost::filesystem::path new_directory("hello");
boost::filesystem::create_directory(new_directory);
}
I then attempted to compile it as I usually have done with the following command.
$ clang++ test.cpp -o test -lboost_system -lboost_filesystem
I received the following error.
test.cpp:3:10: fatal error: 'boost/filesystem.hpp' file not found
#include <boost/filesystem.hpp>
This is how I have always compiled projects that link Boost in the past. I'm assuming that I have probably forgotten a step along the way that allows clang to search a specific path to dynamically link the libraries. What should I change in order for this compilation command to work?
For me, boost has been compiled and installed into a subdirectory of my home directory, so you'll need to modify the paths as appropriate for your homebrew installation:
flags="-std=c++1z -I/${HOME}/local/include -L${HOME}/local/lib -lboost_filesystem -lboost_system"
c++ ${flags} -o jared jared.cpp
First get the location of boost by doing the following:
brew info boost
From the image above, you can see that my location is
/usr/local/Cellar/boost/1.66.0
Then, to compile, use the following:
c++ -I /usr/local/Cellar/boost/1.66.0 main.cpp -o boost
I wanted to use latest g++ compiler(4.9.1) on suse linux, but suse only supports an older g++ version. So, I took a latest source code from one of the gnu mirror sites and compiled it myself. Everything went fine. But when I tried to compile my test code using the built g++, the compilation fails with error,
"/root/home/include/c++/4.9.1/x86_64-unknown-linux-gnu/bits/os_defines.h:39:22: fatal error: features.h: No such file or directory".
I can find a "features.h" in "/root/home/include/c++/4.9.1/parallel", but I feel that it should be there in "/root/home/include/c++/4.9.1/" itself.
I copied "/root/home/include/c++/4.9.1/parallel/features.h" to "/root/home/include/c++/4.9.1/" just to see what happens. Now it complains with error "whcar.h" not found.
Have I missed something.
Here are the steps I followed to build g++.
1. /root/home/gcc_build/objdir# ../gcc-4.9.1/configure --prefix=/root/home/ --disable-multilib
2. /root/home/gcc_build/objdir# make -j16
3. /root/home/gcc_build/objdir# make install
4. /root/home/gcc_build/test# /root/home/bin/g++ --sysroot /root/home -m64 test.cpp
I resolved the issue by removing sysroot option and pointing c++ include and library path to my home directory. One thing I noticed was that the g++ source does not come with libc and c header files, and libc has to be installed seperately. But with sysroot option, g++ was trying to look all the header files in my home directory.
Below is the command I used to successfully compile the code.
/root/home/bin/g++ -I /root/home/include/c++/4.9.1 -L /root/home/lib64 -Wl,--rpath=/root/home/lib64 --std=c++0x -m64 test.cpp
Take a look at the GCC Directory Options. It is important to use the correct "specifier" as well (-isystem, -L, -B, -I etc)
I was trying an openmp code with clang compiler as specified in
http://clang-omp.github.io/
I downloaded the code via git and did make and make install. It successfully installed the clang compiler with openmp support. But when I try to compile a sample code (specified in the above link), I get the following error :
/usr/bin/ld: cannot find -liomp5
I did not specify path to include and lib as mentioned in the site, but I intend to specify them while compiling on command line with -L and -I options.
$clang -I/usr/lib/gcc/i686-linux-gnu/4.6/include -fopenmp test.c -o test
However, I could not find path for iomp5 lib and hence I got the above error. Can someone please tell me how to resolve this?
At first you need to build openmp library libiomp5. You can take the latest source code here
http://llvm.org/svn/llvm-project/openmp/trunk/
I'm trying to call R from c++ on linux via RInside, I compiled R-2.15.1 from source with gcc version 4.5.3 (Debian 4.5.3-1) , I don't have sudo rights to use apt-get install. I'm using OpenBlas and a system optimized lapack. The blas and lapack libraries work fine for many scalapack applications
I installed R with
./configure --with-blas="-I/lib/OpenBLAS-v0.2.3-0/xianyi-OpenBLAS-48f075c/install/include -L/lib/OpenBLAS-v0.2.3-0/xianyi-OpenBLAS-48f075c/install/lib -lopenblas -lgfortran" --with-lapack="/usr/lib/liblapack.so -lgfortran" --enable-BLAS-shlib=yes --enable-R-shlib --enable-R-static-lib --prefix= .
which installed and runs fine,I ran make check with no errors, also all the packages (Rcpp and RInside) installed fine..
however when i use the given RInside makefile , the basic hello world example from /standard/rinside_sample0.cpp compiles! but it does not run and i get the following error
./rinside_sample0: error while loading shared libraries: libRblas.so: cannot open shared object file: No such file or directory
the file libRblas.so exists and is in the R/lib folder,
when i try to link it manually with the g++ command the make file creates or linking as follows i get a segmentation fault
/R/lib/libRblas.so ./hello_world
Segmentation fault
EDIT: heres how the example make file tries to compile an example, (which compiles fine) but won't run with the above missing libRblas.so error
g++ -I/nfs/user03/jimmie21/libs/lib64/R/include -I/nfs/user03/jimmie21/libs/lib64/R/library/Rcpp/include -I/nfs/user03/jimmie21/libs/lib64/R/library/RInside/include -g -O2 -Wall -I/usr/local/include hello_world.cpp -L/nfs/user03/jimmie21/libs/lib64/R/lib -lR -L/nfs/user03/jimmie21/libs/lib64/R/lib -lRblas -L/nfs/user03/jimmie21/libs/lib64/R/lib -lRlapack -L/nfs/user03/jimmie21/libs/lib64/R/lib -lRblas -L/nfs/user03/jimmie21/libs/lib64/R/library/Rcpp/lib -lRcpp -Wl,-rpath,/nfs/user03/jimmie21/libs/lib64/R/library/Rcpp/lib -L/nfs/user03/jimmie21/libs/lib64/R/library/RInside/lib -lRInside -Wl,-rpath,/nfs/user03/jimmie21/libs/lib64/R/library/RInside/lib -o hello_world
Couple of things:
Reproducible examples, please
You have a non-standard setup
With the script from 1), try it on a standard setting as that is how Rcpp / RInside get developed and tested (on Ubuntu / Debian)
The Rcpp test suite now contains almost 800 unit tests from around 350 unit test functions. These do not seg.fault, so the issue is at your end. Similarly, RInside has dozens of examples in the four examples/ subdirectories. This also works.
It may be as easy as tweaking the Makefile / Makevars files to make sure you get your libraries in all cases. But we can't tell as there is nothing reproducible here.
Edit If you want to link with libRblas.so then you have a completely non-standard setup as the R packages for Debian / Ubuntu as use the external BLAS. Again, not an RInside issue.
I fixed the problem by adding the R install path lib ../R/lib: to the beginning of LD_LIBRARY_PATH after that all the examples compiled and run fine