How to build boost with mpi support on homebrew? - macos

According to this post (https://github.com/mxcl/homebrew/pull/2953), the flag "--with-mpi" should enable boost_mpi build support for the related homebrew formula, so I am trying to install boost via homebrew like this:
brew install boost --with-mpi
However, the actual boost mpi library is not being build and can not be found.
There is currently some work being done around this, according to: https://github.com/mxcl/homebrew/pull/15689
In summary, I can currently build boost, but it seems the "--with-mpi" flag is being ignored. Could someone please check, if I should be able to build boost (with mpi support) on Mac OS X Mountain Lion (10.8)?
The (verbose) output generates these lines:
MPI auto-detection failed: unknown wrapper compiler mpic++
Please report this error to the Boost mailing list: http://www.boost.org
You will need to manually configure MPI support.
warning: skipping optional Message Passing Interface (MPI) library.
note: to enable MPI support, add "using mpi ;" to user-config.jam.
note: to suppress this message, pass "--without-mpi" to bjam.
note: otherwise, you can safely ignore this message.
Not sure how exactly I can fix this and get the mpi stuff to be build - any ideas?

Just in case this helps anyone else along the line, here's how I fixed this. The main error is MPI auto-detection failed: unknown wrapper compiler mpic++, any typing mpic++ at the command line verified that it was not working properly for me. I used brew to install open-mpi, but the same error was showing in the verbose output for installing boost. A run of brew doctor showed that openmpi was not linked properly, so I fixed those errors and reran brew -v install boost --with-mpi --without-single and it finally built and installed all of the libraries without a problem

To anyone that comes across this, the package migrated to boost-python and boost-mpi separate from boost. Use brew install boost-mpi

Just get it worked on OSX 10.11.5. I've tried brew, but with no luck.
Suppose you already have gcc installed. Here are what I've done:
1. Find and disable (but do not remove) clang
clang alway cause headaches. There would be a lot of warnings when building Boost.
which clang, which should give you /usr/bin/clang
Rename it: sudo mv clang clang_mac_remove, also for clang++: sudo mv clang++ clang++_mac_remove. You can change the names back if you need them in future.
2. Install OpenMPI
If you already installed using brew, uninstall first. Becasue it would have used clang as the compiler wrapper by default. You need to change the wrapper to gcc.
Download the package.
Specify the wrapper compiler to gcc and g++:
./configure CC=gcc CXX=g++ F77=ifort FC=ifort --prefix=/usr/local
Below may take a long time.
make all
sudo make install
Reference: https://wiki.helsinki.fi/display/HUGG/Open+MPI+install+on+Mac+OS+X
3. Install Boost MPI
Download the package.
Run ./bootstrap.sh (can open it first and specify the toolset to gcc, otherwise, the default option is darwin for mac).
Add using mpi ; in project-config.jam file. Then ./b2 —with-mpi will only build the mpi library.
Then, all built libraries can be found in the folder ~/Downloads/boost_1_61_0/stage/lib.
Copy or move them to /usr/local/lib or any other commonly used library path.
Reference: http://www.boost.org/doc/libs/1_61_0/doc/html/mpi/getting_started.html
4. Compile with Boost MPI
LIBRARY DIR = -L/usr/local/lib
INCLUDE = -I/usr/local/include/
LINKER = -lboost_mpi -lboost_serialization
e.g.
mpic++ -std=c++11 -I/usr/local/include/ -c boost_test.cpp -L/usr/local/lib -lboost_mpi -lboost_serialization
Good luck!

Related

OpenMP on macOS Mojave

I installed the gcc compiler via xcode-select --install but the version installed is 4.2.1 then it isn't possible to use the OpenMp flag -fopenmp for compile the source code.
I tried to install the compile via Homebrew and link this to the gcc exported but it doesn't work. I tried to install gcc building the latest GNU release but after building the operative system asked me if I would install gcc using xcode-select --install.
Moreover, I follow the answer to this question but I have this error:
Error: No available formula with the name "clang-omp"
Is there any solution or suggestion I can follow to execute the OpenMP code on my Mac and on any unix-like device without having to install particular dependencies because in this answer there is a solution but the user can install dependencies?
OpenMP code can be compiled with AppleClang on mojave. Xcode includes an openmp-aware preprocessor which must be invoked.
You must have an omp installed; libomp is the most common. I have also used libiomp5.
Adjust the flags in cmake to point to your openmp solution.:
cmake .. -DCMAKE_C_COMPILER="clang" -DCMAKE_CXX_COMPILER="clang++" -DOpenMP_C_FLAGS=-fopenmp=lomp -DOpenMP_CXX_FLAGS=-fopenmp=lomp -DOpenMP_C_LIB_NAMES="libomp" -DOpenMP_CXX_LIB_NAMES="libomp" -DOpenMP_libiomp5_LIBRARY="/opt/local/lib/libomp.dylib" -DOpenMP_CXX_FLAGS="-Xpreprocessor -fopenmp /opt/local/lib/libomp.dylib -I/opt/local/include" -DOpenMP_CXX_LIB_NAMES="libomp" -DOpenMP_omp_LIBRARY=/opt/local/lib/libomp.dylib -DOpenMP_C_FLAGS="-Xpreprocessor -fopenmp /opt/local/lib/libomp.dylib -I/opt/local/include"
Similar flags for libiomp5: See this line.
Thanks to Richard answer, I was able to compile a project that uses OpenMP on Mojave. I'm adding this answer because some of his flags are currently wrong or useless.
-DOpenMP_C_LIB_NAMES "libomp"
-DOpenMP_CXX_LIB_NAMES "libomp"
-DOpenMP_C_FLAGS "-Xpreprocessor -fopenmp -I/usr/local/include"
-DOpenMP_CXX_FLAGS "-Xpreprocessor -fopenmp -I/usr/local/include"
-DOpenMP_omp_LIBRARY "/usr/local/lib/libomp.dylib"
-DOpenMP_libomp_LIBRARY "/usr/local/lib/libomp.dylib"
libomp was installed with brew install libomp.

Can't compile with gcc-4.9

I eventually want to use valgrind to find what is causing the occasional bizarre output in a C program which refines a model against experimental data using OpenMP parallel programming.
To avoid the use of the nominal gcc (ie clang) compiler, I used brew to install gcc-4.9 on my MacPro running Yosemite (OS x 10.10.5). However, when trying to compile my program with gcc-4.9, with or without -fopenmp, I get numerous error messages of the type:
/var/folders/qc/1j0gr_l48xnfd9001s6tt6f80000gn/T//ccRxnrnU.s:30597:suffix
or operands invalid for `movq'
I have no idea what the problem triggering these error messages is. Can anyone help?
The following summarises what was worked out in the comments section and did lead to the issue being resolved. Not all steps may be necessary, but most are probably good practice.
Step 1 - Clean up
If you have been trying lots of different, potentially incompatible, methods to get OpenMP set up, it is probably a good idea to clean them up first. So, something like:
brew rm --force gcc # or maybe gcc#4.9
Step 2 - Update Xcode and Command Line Tools
If you have upgraded macOS since installing Xcode, it is probably advisable to update Xcode and its "Command Line Tools"
Consider uninstalling and re-installing Xcode - it is available for free from the App Store.
Update/install the "Command Line Tools" after installing/updating with:
xcode-select --install
Step 3 - Install gcc
Now, try installing gcc afresh, ensuring that you use the --without-multilib option:
brew install gcc#4.9 --without-multilib
Hopefully you can now compile OpenMP code with:
/usr/local/bin/gcc -fopenmp program.c -o program
I am unsure exactly why the --without-multilib option is needed and prefer to quote #hristo-iliev:
Multilib usually refers to the coexistence of both 64-bit and 32-bit
versions of each library so that 32-bit software could be run on
64-bit OS. In the GCC case that probably refers to having all GCC
runtime libraries in "fat" Mach-O format, i.e. versions for both i386
and x86_64 in the same shared library file. It could be that libgomp
(the GNU OpenMP runtime library) cannot be built in such a way.
See this question.
Keywords: gcc, g++, GNU Compiler, OpenMP, fopenmp, -fopenmp, Xcode, multilib, Command Line Tools, macOS, OSX, homebrew, brew

fatal error: 'omp.h' file not found

I'm trying to compile my OpenMP program, but it doesn't work, this error message shows:
fatal error: 'omp.h' file not found
I've tried the solutions for this problem here, but nothing worked with me.
please help
I'm Mac user
You probably need to reinstall with:
brew reinstall gcc --without-multilib
Then you need to make sure you use the homebrew version of gcc (rather than anything Apple supplies) by running gcc-5 rather than plain gcc. You can check its name and version by running the following because homebrew normally always installs everything to /usr/local/bin:
ls /usr/local/bin/gcc*
Finally, you need to add the -fopenmp flag to your compiler invocation to tell the compiler to do the OpenMP thing.
So, your command will look like:
gcc-5 -fopenmp program.c -o program

omp.h not found, OS X Yosemite not using newest gcc version

I am trying to build GraphChi on OS X Yosemite but get the following error:
fatal error: 'omp.h' file not found
From this question - How to include omp.h in OS X? - I learned that Yosemite uses Clang instead of gcc, which does not include omp.h.
$ which gcc
/usr/bin/gcc
$ gcc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 6.0 (clang-600.0.56) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin14.1.0
Thread model: posix
Next, I installed gcc via Homebrew
$ brew info gcc
gcc: stable 4.9.2 (bottled)
http://gcc.gnu.org
/usr/local/Cellar/gcc/4.9.2_1 (1092 files, 177M)
Built from source with: --without-multilib
and updated $PATH to include the path to the new gcc version
$ echo $PATH
/usr/local/Cellar/gcc/4.9.2_1:usr/local/bin:/opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin
however, gcc -v and which gcc still point to the old version, and building GraphChi still doesn't work due to the missing omp.h file
Does anyone know what else I need to do?
Update
locate omp.h returned:
/usr/local/Cellar/apple-gcc42/4.2.1-5666.3/lib/gcc/i686-apple-darwin11/4.2.1/include/omp.h
/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include/omp.h
/usr/local/Cellar/gfortran/4.8.2/gfortran/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2/include/omp.h
my ~/.profile:
export PATH=/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include:/usr/local/Cellar/gcc/4.9.2_1/bin:usr/local/bin:/opt/local/bin:/opt/local/sbin:$PATH
I solved this with installing gcc with homebrew:
brew install gcc --without-multilib
and then building the source code with
CC=gcc-5 CXX=g++-5 cmake ..
CC=gcc-5 CXX=g++-5 make -j7
Once you have installed gcc-4.9 with homebrew, it will automatically be in your path. To use OpenMP, you just need to make sure you are using the newly installed gcc-4.9, and it will be able to find omp.h.
In the case of GraphChi, you will have to go change line 3 of the Makefile to be gcc-4.9. From there, running make should just work. They describe this in their README, but at least the version they describe is out of date https://github.com/GraphChi/graphchi-cpp#problems-compiling-on-mac.
clang does not support OpenMP yet. Also gcc by default links to Apple's LLVM clang compiler (not the GCC installed from brew).
Instead gcc-4.9 would link to GCC. I think if -fopenmp is specified omp.h is included automatically.
It is possible to manually build a version of clang with OpenMP support, see http://clang-omp.github.io
You shouldn't add the include path to PATH; instead, specify it as CFLAGS, including the -I option. You can export the CFLAGS variable, or set it on the fly.
Depending on how you compile things, you could do
CFLAGS=-I/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include/omp.h gcc <whatever>
Of course, in this case you can specify it directly on the gcc command (as -I/usr/local/....), but the CFLAGS variable also works with configure (as configure often won't have an option to specify where it should look for specific include files); probably with make, or even for those installing a Python package: CFLAGS=-I... pip install <some-package>.
Other flags to consider are
CXXFLAGS: C++ specific pre-processor flags
LDFLAGS: linker specific flags (e.g. LDFLAGS=-L/some/path/... for linking with dynamic libraries).
CC: specify the C compiler to use. This is an easy way to avoid the built-in gcc alias for clang on OS X. Just use CC=/usr/local/bin/gcc-4 make or similar.
CXX: specify the C++ compiler to use.

Since gcc on mac doesn't support openmp, what can I do to let it support?

At the first,I used the default gcc on my mac.but it does't support openmp.
using "gcc -v",I get gcc 4.2.1
So, I used brew to install gcc. When it is done, using the "gcc -v",it has no changes.
the brew give tips to me "openmp may not be supported,using "brew reinstall gcc --without-muli"??
I don't remember the "muli???" accurately.I try that,but It doesn't help.
So, this is my question: What can I do to make my gcc to support openmp in my macbook?
Brew will install gcc under a slightly different name to not clobber the existing gcc. The easiest way to check for other gcc's is to type gcc- and then hit the TAB key to see what completions there are. I believe brew's current gcc is 4.9.1, so after installing gcc with brew you should be able to access it with gcc-4.9.

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