Difficulty linking Boost 1.60 on OS X after installing via Homebrew - c++

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

Related

OpenBlas and g++

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

SDL2_image not found

I am trying to compile the following code which has the headers:
#include <SDL2/SDL.h>
#include <SDL2_image/SDL_image.h>
However after running the following makefile:
g++ -std=c++11 src/main.cpp -lSDL2 -lSDL2_image
I get the following error:
fatal error: SDL2_image/SDL_image.h: No such file or directory
#include <SDL2_image/SDL_image.h>
Any suggestions? Not entirely sure about my installation of SDL_image. I am running this on Ubuntu.
This problem can be solved through installing libsdl2-image-dev package:
apt install libsdl2-image-dev
Run apt-file search SDL_image.h
The result will tell you the location of the include file.
For instance, /usr/include/SDL2/SDL_image.h was returned.
So, when you want to include SDL_image.h, write everything after the include/ in between < >.
Thus, includes should look like the following:
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
See the question's comments for the original discussion regarding this solution.
From SDL documentation, it says that add 'lSDL_image' to the end of the compile line.
cc -o myprogram mysource.o `sdl-config --libs` -lSDL_image
or
gcc -o myprogram mysource.c `sdl-config --libs` -lSDL_image
Here is the reference -> https://www.libsdl.org/projects/docs/SDL_image/SDL_image.html
Section 2.2 Compiling.
So for SDL2, you just need to change 'lSDL_image' to 'lSDL2_image'.
For Windows + SDL2-2.0.8 + SDL_image-2.0.4 + Codeblocks you've got the add both Runtime Binaries and Development Libraries to the compiler and linker. Or else, you'll get the error SDL2_image not found, even with having the dll in your program's directory, this occurs. Hopefully others find this helpful; I had to figure it out myself. Example: If your resources are separate, you'll be adding the two plus your standard SDL2 paths to your compiler and linker. Warning: SDL2_image.h has it's headers assuming that the headers are in the same folder as the SDL2 framework. If you get errors about the image header, include the sub-folder SDL2 from SDL framework in the path and then you should be including SDL2 in the program as: include <SDL.h> rather than include <SDL2/SDL.h>.

why self built g++ compiler fails to compile my code

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)

Compiling Boost example projects with Cygwin + gcc

While trying to compile the boost asio example project
async_tcp_echo_server.cpp
I get errors like the following:
__MSABI_LONG was not declared in this file scope
BOOST_ASIO_NATIVE_ERROR(ERROR_BROKEN_PIPE)
__MSABI_LONG was not declared in this file scope
BOOST_ASIO_NATIVE_ERROR(ERROR_OPERATION ABORTED)
This is with Boost 1.55.0 and gcc version 4.8.3
boost was compiled with gcc and the following commands
./bootstrap.sh
./b2 cxxflags="-D__USE_W32_SOCKETS -D_WIN32_WINNT=0x0501
./b2 install
I attempted to compile the sample project with
gcc -std=C++11 -D__USE_W32_SOCKETS -D_WIN32_WINNT=0x0501 -I C:\boost_1_55_0 C:\boost_1_55_0\boost\asio.hpp async_tcp_echo_server.cpp
I know this is kind of old thread.
I managed to fix it by reinstalling the boost lib via Cygwin setup_x86.exe.
The version I installed is 1.57. And you don't have to put -D option in the command line.
Hope this may help.
1_57 version from cygwin setup doesn't help for me, it gives me fd_set errors.
This is what I tried to make the boost example code work:
add #define __MSABI_LONG(x) x at the top. - chilly, I know :)
add these flags to g++:-D_WIN32_WINNT=0x0501 -D__USE_W32_SOCKETS -std=c++11 -lboost_system -lws2_32
Voila!

Using the c++ Boost regex libraries in Arch Linux

I'm having trouble building a simple c++ program that tests out regex's from the boost library. The problem that I'm having is occurring in the linking stage and I don't know enough to fix the error on my own.
In the .cpp program that uses regexes I used the following include line.
#include <boost/regex.hpp>
I don't know enough to figure out what command I should use to build the program using g++. I tried using the following command line (and variations of it) to build the program.
g++ -I/usr/include/regex -L/usr/lib -llibboost_regex main.cpp -o regex_test
Other information that might be relevant:
Operating system: Arch linux
g++ version: 4.6.2 20120120 (prerelease)
Any help would be appreciated.
Assume you have installed Boost with the boost and boost-libs packages,
The header <boost/regex.hpp> should exist in /usr/include/boost/regex.hpp. You don't need to use any -I flags since /usr/include should be included by default.
You shouldn't need the -L flag either since /usr/lib should also be included by default when linking.
When using the -l flag to link with a library libfoo.so, the leading "lib" part should be removed.
The command line should therefore be:
g++ main.cpp -o regex_test -lboost_regex