I would like to test the Boost.Log library. Unfortunately, I get link errors.
I use Arch Linux, and I installed Boost headers and libraries via built-in package manager pacman:
boost 1.54.0-3
boost-libs 1.54.0-2
When compiling the simple example from official site via g++ log.cpp -lboost_log -lpthread, I get the following errors:
log.cpp:(.text+0x42): undefined reference to `boost::log::v2s_mt_posix::trivial::logger::get()'
log.cpp:(.text+0x9b): undefined reference to `boost::log::v2s_mt_posix::trivial::logger::get()'
...
I've read Why my application fails to link with Boost.Log?, but I couldn't solve the link errors. It only gives me the hint that the library where boost::log::v2s_mt_posix::trivial::logger::get() is in was linked statically. But under directory /usr/lib/ there are only dynamically linked Boost libraries with extension .so.
Maybe, someone has a clue what's going wrong here.
Thank you.
You need to define BOOST_LOG_DYN_LINK:
g++ -DBOOST_LOG_DYN_LINK blog.cpp -lboost_log -lpthread
If you are using cmake then:
find_package(Boost REQUIRED COMPONENTS system log)
target_link_libraries(credential ${Boost_SYSTEM_LIBRARY} ${Boost_LOG_LIBRARY})
and use:
#define BOOST_LOG_DYN_LINK 1
Related
After reading a lot of SO questions on the matter, I just couldn't get it to work. I downloaded boost_1_60_0, then I ran the commands to build it:
sudo ./bootstrp.sh --prefix=/home/ricardo/boostlib
sudo ./b2 install -j8
I even tried running b2 like this:
sudo ./b2 install -j8 architecture=x86 address-model=64
Does not matter. The error is always the same:
main.cpp:(.text+0x7e): undefined reference to `boost::system::generic_category()'
main.cpp:(.text+0x8a): undefined reference to `boost::system::generic_category()'
main.cpp:(.text+0x96): undefined reference to `boost::system::system_category()'
Yeah, I know. Linking error, should run with -lboost_system and all. Yeah, you should put -L/home/ricardo/boostlib/lib. I know.
This is what my CMake looks like:
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -L/home/ricardo/boostlib/lib -lboost_system -Wl,--verbose")
include_directories("/home/ricardo/boostlib/include")
You might be asking: What's the output of -Wl,--verbose? Well, surprisingly enough, libboost_system.so has been found:
attempt to open /home/ricardo/boostlib/lib/libboost_system.so succeeded
-lboost_system (/home/ricardo/boostlib/lib/libboost_system.so)
Okay. The library was found. I'm still trying to find some alternatives, nothing seems to work so far. So, even though I'm linking it against boost, and boost_system has been found, the program still does not compile due to... why? Can someone explain me?
Edit: How to link C++ program with Boost using CMake seems to be working. Though I still would like to know why my method does not work, and what should I do when I want to link against boost using just the g++ compiler, without CMake and Make. I've been able to link against Openblas succesfully before, so I wonder why it isn't working with Boost.
Edit2: This is the g++ command I got after running make VERBOSE=1, now I can see that the sources are being put AFTER the dependencies.
-std=c++11 -L/home/ricardo/boostlib/lib -lboost_system CMakeFiles/prophet-service.dir/main.cpp.o -o prophet-service -rdynamic
And this is my current CMake file:
cmake_minimum_required(VERSION 3.2)
project(prophet-service)
set(SOURCE_FILES
main.cpp)
include_directories("/home/ricardo/boostlib/include")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -L/home/ricardo/boostlib/lib -lboost_system")
add_executable(prophet-service ${SOURCE_FILES})
It also seems that I don't have the libbost_system.a file. At least now I know that I need the .a file instead of the .so file.
Are you linking in the right order? The thing that HAS the dependency needs to go before the thing that SATISFIES the dependency.
You need to link version of the library with extension .a because linker requires this extension (used for static libraries) and not .so which is used for shared libraries (the same of dll for Windows).
For example, if I search for libboost_system.a on my Ubuntu operating system I find the following:
frar#Home-PC:~$ locate libboost_system.a
/home/frar/Documents/SVILUPPO/boost_1_59_0/bin.v2/libs/system/build/gcc-4.8/release/link-static/threading-multi/libboost_system.a
/home/frar/Documents/SVILUPPO/boost_1_59_0/stage/lib/libboost_system.a
/usr/lib/x86_64-linux-gnu/libboost_system.a
I'm trying to compile a program on Ubuntu 11.10 that uses the Boost libraries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
undefined reference to boost::system::system_category()
What is it that I do wrong?
The boost library you are using depends on the boost_system library. (Not all of them do.)
Assuming you use gcc, try adding -lboost_system to your compiler command line in order to link against that library.
Linking with a library that defines the missing symbol (-lboost_system) is the obvious solution, but in the particular case of Boost.System, a misfeature in the original design makes it use boost::system::generic_category() and boost::system::system_category() needlessly. Compiling with the flag -DBOOST_SYSTEM_NO_DEPRECATED disables that code and lets a number of programs compile without requiring -lboost_system (that link is of course still needed if you explicitly use some of the library's features).
Starting from Boost 1.66 and this commit, this behavior is now the default, so hopefully fewer and fewer users should need this answer.
As noticed by #AndrewMarshall, an alternative is to define BOOST_ERROR_CODE_HEADER_ONLY which enables a header-only version of the code. This was discouraged by Boost as it can break some functionality. However, since 1.69, header-only seems to have become the default, supposedly making this question obsolete.
Another workaround for those who don't need the entire shebang: use the switch
-DBOOST_ERROR_CODE_HEADER_ONLY.
If you use CMake, it's add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY).
The above error is a linker error... the linker a program that takes one or more objects generated by a compiler and combines them into a single executable program.
You must add -lboost_system to you linker flags which indicates to the linker that it must look for symbols like boost::system::system_category() in the library libboost_system.so.
If you have main.cpp, either:
g++ main.cpp -o main -lboost_system
OR
g++ -c -o main.o main.cpp
g++ main.o -lboost_system
When using CMAKE and find_package, make sure it is :
find_package(Boost COMPONENTS system ...)
and not
find_package(boost COMPONENTS system ...)
Some people may have lost hours for that ...
I got the same Problem:
g++ -mconsole -Wl,--export-all-symbols -LC:/Programme/CPP-Entwicklung/MinGW-4.5.2/lib -LD:/bfs_ENTW_deb/lib -static-libgcc -static-libstdc++ -LC:/Programme/CPP-Entwicklung/boost_1_47_0/stage/lib \
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj \
-o D:/bfs_ENTW_deb/bin/filesystem.exe -lboost_system-mgw45-mt-1_47 -lboost_filesystem-mgw45-mt-1_47
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj:main_filesystem.cpp:(.text+0x54):
undefined reference to `boost::system::generic_category()
Solution was to use the debug-version of the system-lib:
g++ -mconsole -Wl,--export-all-symbols -LC:/Programme/CPP-Entwicklung/MinGW-4.5.2/lib -LD:/bfs_ENTW_deb/lib -static-libgcc -static-libstdc++ -LC:/Programme/CPP-Entwicklung/boost_1_47_0/stage/lib \
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj \
-o D:/bfs_ENTW_deb/bin/filesystem.exe -lboost_system-mgw45-mt-d-1_47 -lboost_filesystem-mgw45-mt-1_47
But why?
When I had this, problem, the cause was the ordering of the libraries. To fix it, I put libboost_system last:
g++ mingw/timer1.o -o mingw/timer1.exe -L/usr/local/boost_1_61_0/stage/lib \
-lboost_timer-mgw53-mt-1_61 \
-lboost_chrono-mgw53-mt-1_61 \
-lboost_system-mgw53-mt-1_61
This was on mingw with gcc 5.3 and boost 1.61.0 with a simple timer example.
in my case, adding -lboost_system was not enough, it still could not find it in my custom build environment. I had to use the advice at Get rid of "gcc - /usr/bin/ld: warning lib not found" and change my ./configure command to:
./configure CXXFLAGS="-I$HOME/include" LDFLAGS="-L$HOME/lib -Wl,-rpath-link,$HOME/lib" --with-boost-libdir=$HOME/lib --prefix=$HOME
for more details see Boost 1.51 : "error: could not link against boost_thread !"
...and in case you wanted to link your main statically, in your Jamfile add the following to requirements:
<link>static
<library>/boost/system//boost_system
and perhaps also:
<linkflags>-static-libgcc
<linkflags>-static-libstdc++
When I am including the asio header:
#include <boost/asio.hpp>
I got the error:
undefined reference to boost::system::generic_category()
So I read that I had to link to boost_system which I did. But now it gives the error::
cannot find -lboost_system
Why can it not find boost_system. I'm using Codeblocks on Windows.
boost is a separate library that needs to be installed on you building machine.
Please follow these instructions to install:
http://www.boost.org/doc/libs/1_55_0/doc/html/bbv2/installation.html
http://www.boost.org/
After installation your application needs to be able to find it if it is not installed in a standard location.
you will need to supply the header and lib directories to the build process.
g++ source source.cpp -I/path to boost headers -L path to boost libs -lboost_system
Look inside you libs directory to be sure that you have boost_system. It is possible depending on the build that you may only have boost_system-mt
I am trying to include Boost libraries in my project and have been facing issues in the same. I am on Ubuntu 12.10 with Codeblocks IDE and tried installing the libraries manually reading instructions from the site, but was getting error's with header as well as to-be-built-before-use libraries.
I then installed the libraries via terminalby sudo apt-get install libboost-all-dev. After this, in my programs on Codeblocks, I can include headers like #include <boost/regex.hpp> but when I try to include the header for the Filesystem library ( #include "boost/filesystem/operations.hpp" ), I am getting the following error:
/usr/include/boost/system/error_code.hpp|214|undefined reference to boost::system::generic_category()'|
I am not sure how to resolve this error (specifically in Codeblocks on Linux). I really could use some help here.
Compiler : Gcc
Program code: Only tried inlcuding the above file system operations.hpp file.
Build log from Codeblocks:
Build started on: 20-11-2012 at 18:02.53
Build ended on: 20-11-2012 at 18:02.54
-------------- Build: Debug in libopenFrameworks ---------------
Target is up to date.
-------------- Build: Debug in reader1 ---------------
make -s -f Makefile Debug
linking i686 bin/reader1_debug linux
obj/i686Debug/src/testApp.o: In function `__static_initialization_and_destruction_0':
/usr/include/boost/system/error_code.hpp:214: undefined reference to `boost::system::generic_category()'
/usr/include/boost/system/error_code.hpp:215: undefined reference to `boost::system::generic_category()'
/usr/include/boost/system/error_code.hpp:216: undefined reference to `boost::system::system_category()'
obj/i686Debug/src/main.o: In function `__static_initialization_and_destruction_0':
/usr/include/boost/system/error_code.hpp:214: undefined reference to `boost::system::generic_category()'
/usr/include/boost/system/error_code.hpp:215: undefined reference to `boost::system::generic_category()'
/usr/include/boost/system/error_code.hpp:216: undefined reference to `boost::system::system_category()'
collect2: ld returned 1 exit status
make: *** [bin/reader1_debug] Error 1
Process terminated with status 2 (0 minutes, 1 seconds)
6 errors, 0 warnings
You should link in the libboost_system library. I am not sure about codeblocks, but the g++ command-line option on your platform would be
-lboost_system
Depending on the boost version libboost-system comes with the -mt suffix which should indicate the libraries multithreading capability.
So if -lboost_system cannot be found by the linker try -lboost_system-mt.
This answer actually helped when using Boost and cmake.
Adding add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY) for cmake file.
My CMakeLists.txt looks like this:
cmake_minimum_required(VERSION 3.12)
project(proj)
set(CMAKE_CXX_STANDARD 17)
set(SHARED_DIR "${CMAKE_SOURCE_DIR}/../shared")
set(BOOST_LATEST_DIR "${SHARED_DIR}/boost_1_68_0")
set(BOOST_LATEST_BIN_DIR "${BOOST_LATEST_DIR}/stage/lib")
set(BOOST_LATEST_INCLUDE_DIR "${BOOST_LATEST_DIR}/boost")
set(BOOST_SYSTEM "${BOOST_LATEST_BIN_DIR}/libboost_system.so")
set(BOOST_FS "${BOOST_LATEST_BIN_DIR}/libboost_filesystem.so")
set(BOOST_THREAD "${BOOST_LATEST_BIN_DIR}/libboost_thread.so")
set(HYRISE_SQL_PARSER_DIR "${SHARED_DIR}/hyrise_sql_parser")
set(HYRISE_SQL_PARSER_BIN_DIR "${HYRISE_SQL_PARSER_DIR}")
set(HYRISE_SQL_PARSER_INCLUDE_DIR "${HYRISE_SQL_PARSER_DIR}/src")
set(HYRISE_SQLPARSER "${HYRISE_SQL_PARSER_BIN_DIR}/libsqlparser.so")
include_directories(${CMAKE_SOURCE_DIR} ${BOOST_LATEST_INCLUDE_DIR} ${HYRISE_SQL_PARSER_INCLUDE_DIR})
set(BOOST_LIBRARYDIR "/usr/lib/x86_64-linux-gnu/")
set(Boost_USE_STATIC_LIBS OFF)
set(Boost_USE_MULTITHREADED ON)
set(Boost_USE_STATIC_RUNTIME OFF)
add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY)
find_package(Boost 1.68.0 REQUIRED COMPONENTS system thread filesystem)
add_executable(proj main.cpp row/row.cpp row/row.h table/table.cpp table/table.h page/page.cpp page/page.h
processor/processor.cpp processor/processor.h engine_instance.cpp engine_instance.h utils.h
meta_command.h terminal/terminal.cpp terminal/terminal.h)
if(Boost_FOUND)
include_directories(${Boost_INCLUDE_DIRS})
target_link_libraries(proj PUBLIC Boost::system Boost::filesystem Boost::thread ${HYRISE_SQLPARSER})
endif()
It's a linker problem. Include the static library path into your project.
For Qt Creator open the project file .pro and add the following line:
LIBS += -L<path for boost libraries in the system> -lboost_system
In my case Ubuntu x86_64:
LIBS += -L/usr/lib/x86_64-linux-gnu -lboost_system
For Codeblocks, open up Settings->Compiler...->Linker settings tab and add:
boost_system
to the Link libraries text widget and press OK button.
I searched for a solution as well, and none of the answers I encountered solved the error, Until I found the answer of "ViRuSTriNiTy" to this thread: Undefined reference to 'boost::system::generic_category()'?
according to that answer, try to add these lines to your cmake file:
find_package(Boost 1.55.0 REQUIRED COMPONENTS system filesystem)
include_directories(... ${Boost_INCLUDE_DIRS})
link_directories(... ${Boost_LIBRARY_DIRS})
target_link_libraries(... ${Boost_LIBRARIES})
Same problem on building a simple boost example, solved after i changed the g++ compiler flag from -std=c++14 to -std=c++11.
And I noticed that it's a C++11 Example...
I had the same problem and also use Linux Mint (as nuduoz) . I my case problem was solved after i added boost_system to GCC C++ Linker->Libraries.
You could come across another problem. After installing Boost on the Linux Mint I've had the same problem. Linking -lboost_system or -lboost_system-mt haven't worked because library have had name libboost_system.so.1.54.0.
So the solution is to create symbolic link to the original file. In my case
sudo ln -s /usr/lib/x86_64-linux-gnu/libboost_system.so.1.54.0 /usr/lib/libboost_system.so
For more information see this question.
g++ -lboost_system -lboost_filesystem userentry.cpp -o userentry
worked perfectly under debian. (boost c++ libraries installed with apt-get).
Il the library is not installed you should give boost libraries folder:
example:
g++ -L/usr/lib/x86_64-linux-gnu -lboost_system -lboost_filesystem prog.cpp -o prog
try
g++ -c main.cpp && g++ main.o /usr/lib/x86_64-linux-gnu/libboost_system.so && ./a.out
/usr/lib/x86_64-linux-gnu/ is the location of the boost library
use find /usr/ -name '*boost*.so' to find the boost library location
In my project I prefer to use header-only libraries. So nothing above was helpful. What did really help is:
add_definitions(-DBOOST_SYSTEM_NO_DEPRECATED)
After testing the proposed solutions described above, I found only these few of lines would work.
I am using Ubuntu 16.04.
cmake_minimum_required(VERSION 3.13)
project(myProject)
set(CMAKE_CXX_STANDARD 11)
add_executable(myProject main.cpp)
find_package(Boost 1.58.0 REQUIRED COMPONENTS system filesystem)
target_link_libraries(myProject ${Boost_LIBRARIES})
I'm trying to compile a program on Ubuntu 11.10 that uses the Boost libraries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
undefined reference to boost::system::system_category()
What is it that I do wrong?
The boost library you are using depends on the boost_system library. (Not all of them do.)
Assuming you use gcc, try adding -lboost_system to your compiler command line in order to link against that library.
Linking with a library that defines the missing symbol (-lboost_system) is the obvious solution, but in the particular case of Boost.System, a misfeature in the original design makes it use boost::system::generic_category() and boost::system::system_category() needlessly. Compiling with the flag -DBOOST_SYSTEM_NO_DEPRECATED disables that code and lets a number of programs compile without requiring -lboost_system (that link is of course still needed if you explicitly use some of the library's features).
Starting from Boost 1.66 and this commit, this behavior is now the default, so hopefully fewer and fewer users should need this answer.
As noticed by #AndrewMarshall, an alternative is to define BOOST_ERROR_CODE_HEADER_ONLY which enables a header-only version of the code. This was discouraged by Boost as it can break some functionality. However, since 1.69, header-only seems to have become the default, supposedly making this question obsolete.
Another workaround for those who don't need the entire shebang: use the switch
-DBOOST_ERROR_CODE_HEADER_ONLY.
If you use CMake, it's add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY).
The above error is a linker error... the linker a program that takes one or more objects generated by a compiler and combines them into a single executable program.
You must add -lboost_system to you linker flags which indicates to the linker that it must look for symbols like boost::system::system_category() in the library libboost_system.so.
If you have main.cpp, either:
g++ main.cpp -o main -lboost_system
OR
g++ -c -o main.o main.cpp
g++ main.o -lboost_system
When using CMAKE and find_package, make sure it is :
find_package(Boost COMPONENTS system ...)
and not
find_package(boost COMPONENTS system ...)
Some people may have lost hours for that ...
I got the same Problem:
g++ -mconsole -Wl,--export-all-symbols -LC:/Programme/CPP-Entwicklung/MinGW-4.5.2/lib -LD:/bfs_ENTW_deb/lib -static-libgcc -static-libstdc++ -LC:/Programme/CPP-Entwicklung/boost_1_47_0/stage/lib \
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj \
-o D:/bfs_ENTW_deb/bin/filesystem.exe -lboost_system-mgw45-mt-1_47 -lboost_filesystem-mgw45-mt-1_47
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj:main_filesystem.cpp:(.text+0x54):
undefined reference to `boost::system::generic_category()
Solution was to use the debug-version of the system-lib:
g++ -mconsole -Wl,--export-all-symbols -LC:/Programme/CPP-Entwicklung/MinGW-4.5.2/lib -LD:/bfs_ENTW_deb/lib -static-libgcc -static-libstdc++ -LC:/Programme/CPP-Entwicklung/boost_1_47_0/stage/lib \
D:/bfs_ENTW_deb/obj/test/main_filesystem.obj \
-o D:/bfs_ENTW_deb/bin/filesystem.exe -lboost_system-mgw45-mt-d-1_47 -lboost_filesystem-mgw45-mt-1_47
But why?
When I had this, problem, the cause was the ordering of the libraries. To fix it, I put libboost_system last:
g++ mingw/timer1.o -o mingw/timer1.exe -L/usr/local/boost_1_61_0/stage/lib \
-lboost_timer-mgw53-mt-1_61 \
-lboost_chrono-mgw53-mt-1_61 \
-lboost_system-mgw53-mt-1_61
This was on mingw with gcc 5.3 and boost 1.61.0 with a simple timer example.
in my case, adding -lboost_system was not enough, it still could not find it in my custom build environment. I had to use the advice at Get rid of "gcc - /usr/bin/ld: warning lib not found" and change my ./configure command to:
./configure CXXFLAGS="-I$HOME/include" LDFLAGS="-L$HOME/lib -Wl,-rpath-link,$HOME/lib" --with-boost-libdir=$HOME/lib --prefix=$HOME
for more details see Boost 1.51 : "error: could not link against boost_thread !"
...and in case you wanted to link your main statically, in your Jamfile add the following to requirements:
<link>static
<library>/boost/system//boost_system
and perhaps also:
<linkflags>-static-libgcc
<linkflags>-static-libstdc++