Boost linking warning - c++

What happened:
I built boost with bootstrap.sh and b2. Installed with ./b2 install
Couldn't figure out how to use it, as I'm a newbie
sudo apt install libboost-dev
Searched online for instructions. I can now link it with no errors
sudo apt purge libboost-dev
There's a warning: "/usr/bin/ld: warning: libboost_system.so.1.58.0, needed by //usr/lib/x86_64-linux-gnu/libmirclient.so.9, may conflict with libboost_system.so.1.66.0"
I'm using boost 1.66. The .a and .so files are in /usr/local/lib
There are some boost 1.58 .a and .so files in /usr/lib/x86_64-linux-gnu
If I use /usr/local/lib/[library] instead of -L/usr/local/lib/ -l[libraries-without-.a] the warning disappears. However, the Makefile gets significantly longer.
My questions: Is the warning serious? How can I get rid of it? How can I use -L command without triggering that warning? Can I delete the boost .a and .so files in /usr/lib/x86_64-linux-gnu? I'm using Ubuntu 16.04 by the way.
Thanks.

Related

Can't use static lib of mongo-cxx-driver on Linux

So I follow the official tutorial for the installation : https://mongodb.github.io/mongo-cxx-driver/mongocxx-v3/installation/
Neverless, I can't use the produced libraries as static.
So I managed to compile the C version of the driver as described, I've enabled the flag --enable-static=yes with the ./configure before doing make && sudo make install and I got the libmongoc-1.0.a and the libbson-1.0.a which are static. So this far, everything it's alright.
Then I have done the cxx version of the driver, except that there is no configuration file as in the C version. So I've juste done a
cmake -DCMAKE_BUILD_TYPE=Release -DBSONCXX_POLY_USE_BOOST=1 -DCMAKE_INSTALL_PREFIX=/usr/local
from the build folder, followed by a make && sudo make install
So I got the libmongocxx.a and the libbsoncxx.a, but when I try to compile with them, I can't run the binary because I got the following error :
error while loading shared libraries: libmongocxx.so._noabi: cannot open shared object file: No such file or directory
So I understand that is because there is some symbols missing and then I need to use the shared library to run the binary but I don't want this to happend, I want the symbols within the binary that I can run it without any LD_PRELOAD.
Any suggestions ?
I had the same issue in an Ubuntu 16.04 and I run a apt-get update & apt-get upgrade and the problem was solved.
It seems that there were some update to the compiler and some libraries that prevent some test from reaching the shared libraries.
I have a similar question, and solved, now I compiled and run my binary with static libs successfully.
I write my build script using newlisp, but the static link options are very helpful, I paste it here.
c++ /to/your/path/site/code/back_end/builder/object/files1.cc.o ... /to/your/path/site/code/back_end/builder/object/files10.cc.o -o bin/site -static-libgcc -static-libstdc++ -L/usr/lib -lpthread -l:libmongocxx.a -l:libbsoncxx.a -l:libmongoc-1.0.a -l:libbson-1.0.a -lrt -lssl -lcrypto -lsasl2 -l:libboost_log.a -l:libboost_log_setup.a -l:libboost_system.a -l:libboost_thread.a -l:libboost_filesystem.a -lcppcms -lbooster -lcurl -ljsoncpp

gfortran "not linked" after installing with 'brew install gcc'

I need to use fortran so I have installed gcc from homebrew
brew install gcc
i couldn't compile my source code so i tried to reinstall
Warning: gcc-6.2.0 already installed, it's just not linked
so i tried to link it
brew link gcc
with this result
Error: Could not symlink bin/gfortran
Target /usr/local/bin/gfortran
already exists. You may want to remove it:
rm '/usr/local/bin/gfortran
so i tried this
brew link --overwrite gcc
which gave me this result
Error: Could not symlink include/c++/6.2.0
/usr/local/include/c++ is not writable.
As i am pretty new to this I'm now stuck but i desperately need to resolve this so i can continue my uni work at home, please help

Linking boost::asio using terminal

I am trying to link boost::asio using terminal (I'm also using a text editor).
What I tried
I did some researches on Internet (I didn't found nothing about my distro) - I found I must install that library by executing the following command on the terminal:
sudo pacman -S libboost-all-dev
This is the output I get:
error: the following package was not found: libboost-all-dev
Final question
How can I install and link correctly boost::asio with my .cpp file?
Notes:
I'm using Archlinux
To find a package in Arch Linux, do:
sudo pacman -Ss boost
This will list packages with the string boost. Or, you can look up on the package website: https://www.archlinux.org/packages/extra/x86_64/boost/
One thing you should understand about boost is that a majority of its modules are header-only; if the linker complains about undefined references then you would have to link the required files. To link boost-asio, you would do
g++ -lboost-system <source> <exe>
How to install boost in Arch Linux
You cannot link libraries inside your *.cpp files. You should enumerate required libraries using the -l option in the g++ command line.
g++ -lboos-asio -lboost-system myfile.cpp -o myapp

Boost librairies not found but compilation is ok

I am trying to use filesystem from boost in c++
It seems the compilation is ok when using
"c++ -c Analyse.c -o Analyse.o -g -W -Wall -L/usr/local/lib -lboost_filesystem -lboost_system"
However I have the following error when trying to execute my code :
"error while loading shared libraries: libboost_filesystem.so.1.54.0: cannot open shared object file: No such file or directory", a find / -iname "libboost_system.so.1.54.0
I had some issues to install boost (I first installed the 1.49 and after that 1.54) so I was wondering if there could be any conflict between the 2 version ?
P.S : btw a "find / -iname "libboost_system.so.1.54.0" gave me the following
/usr/include/boost/boost_1_54_0/bin.v2/libs/system/build/gcc-4.7/release/threading-multi/libboost_system.so.1.54.0
/usr/local/lib/libboost_system.so.1.54.0
Try to add the directory before execution. For example:
LD_LIBRARY_PATH="/usr/local/lib/" ./Analyse.o
I encountered this issue very recently, after a fresh installation of boost. In my case, the solution was to simply run
sudo ldconfig
The explanation is that the system keeps a cache of the installed shared libraries (located in /usr/lib, /lib, /usr/local/lib). When the libraries are changed, or new ones are added, the cache is not updated until ldconfig is run. More details can be found in the ldconfig manual.

libboost-system linker errors when cross-compiling to x86

I'm trying to build a 32-bit application on Ubuntu 11.04 x64. I'm having some issues with the build because of linker errors with libboost. The build statement has -lboost_system in it, but when I try to build I get a bunch of these:
CommunicationModule.cpp:(.text+0x68c1): undefined reference to boost::system::generic_category()
CommunicationModule.cpp:(.text+0x68d7): undefined reference to boost::system::system_category()
Everything I've found on google says I need to link to the boost_system library. One place I found says to try linking to it directly, but when i do locate boost_system the result is empty. When I try doing a sudo apt-get install libboost-system-dev it tells me that it's already installed. I'm kind of at a loss here. The library is installed, but it's not being found by locate?
Can anyone tell me what I need to do to properly link to boost::system? I'm fairly new to linux and the complexities of compilers so any help here would be appreciated.
Update:
Here is the output of dpkg -L libboost-system1.42-dev:
/.
/usr
/usr/share
/usr/share/doc
/usr/share/doc/libboost-system1.42-dev
/usr/share/doc/libboost-system1.42-dev/copyright
/usr/share/doc/libboost-system1.42-dev/NEWS.Debian.gz
/usr/share/doc/libboost-system1.42-dev/README.Debian.gz
/usr/lib
/usr/lib/libboost_system.a
/usr/lib/libboost_system-mt.so
/usr/lib/libboost_system-mt.a
/usr/lib/libboost_system.so
Is there a flag I can use to link to one of these directly? I tried using -L /usr/lib/libboost_system.so and -L /usr/lib/libboost_system-mt.so and neither of those fixed the issue. Same with just adding /usr/lib/libboost_system.a and /usr/lib/libboost_system-mt.a to the build statement.
Here is the compilation line:
g++ -m32 -Wl,-O1 -o UTNaoTool [.o files] -L/usr/lib32 -lqglviewer-qt4 -lqwt-qt4 -lboost_system -lboost_thread -lQtXml -lQtOpenGL -lQtGui -lQtNetwork -lQtCore -lGLU -lpthread
Update 2:
I downloaded boost 1.49 and built everything for 32-bit and that seemed to help. A lot of the errors went away, but now I still have these:
CommunicationModule.cpp:(.text+0x68c1): undefined reference to
boost::system::get_generic_category()
Note that the function is different. So all of my errors are regarding undefined references to get_system_category() and get_generic_category() now. I tried adding a -lboost_filesystem to the build command but that didn't fix this, and I made sure it was referencing the 32-bit library that I built when I built libboost_system.
Looking at my own installation, it seems libboost-system-dev does not install the libraries. Using dpkg to tell me what was installed bz libboost-system-dev I get:
$ dpkg -L libboost-system-dev
/.
/usr
/usr/share
/usr/share/doc
/usr/share/doc/libboost-system-dev
/usr/share/doc/libboost-system-dev/copyright
/usr/share/doc/libboost-system-dev/changelog.gz
Poking around, I think you need to install libboost-system1.48.1 (or some other version).
sudo apt-get install libboost-system1.XX.Y
You can also search fo rthe libraries using the find command, for example, search under /usr for all files starting with libboost_system:
find /usr -name "libboost_system*"
Edit: Since you are cross-compiling from a 64 bit OS to a 32 bit one, you need 32 bit versions of the boost libraries. I would be tempted to set up a small 32 bit virtual machine to do this, rather than cross-compiling all the dependencies.
I had the same problem with boost_serialization here is what i found out after couple of googling..
first this library need to be compiled separately :
so after downloading the boost library ,extract it and execute sudo ./bootstrap.sh' then
sudo ./b2 --with-system
after this step you should be find a result when executing locate boost_system
then to link it manually I did:
both should work
g++ boostexample.cpp -o run /PATH/libboost_serialization.a
g++ boostexample.cpp -o run -L/PATH/ -lboost_serialization
well this is a little work around and I'm still looking for how to link the library properly
I hope this helped :)