I am following the instructions on
http://tayefeh.wordpress.com/2009/07/06/creating-and-using-a-c-shared-library-with-eclipse-cdt-galileo-and-gnu-c-compiler-and-linker/
to build a shared library.
I have got to Step II, bullet point 16 but my attempts to build the project fail with the following error:
**** Build of configuration Debug for project UseDLL ****
make all
Building target: UseDLL
Invoking: GCC C++ Linker
g++ -L"/home/ken/workspace/testlib/Debug" -o"UseDLL" ./src/UseDLL.o -ltestlib -l/home/ken/workspace/testlib/Debug
/usr/bin/ld: cannot find -l/home/ken/workspace/testlib/Debug
collect2: ld returned 1 exit status
make: *** [UseDLL] Error 1
Can anyone advise why the build is failing? The directory does exist and ls shows
[ken#localhost Debug]$ ls /home/ken/workspace/testlib/Debug/
libtestlib.so TestClass.o
If it helps, I am running CentOS 6.3.
Thanks,
Ken
You should remove this:
-l/home/ken/workspace/testlib/Debug
It makes g++ look for a library of that name.
Related
I'm trying to install the cccfiles library for Eclipse, but I keep getting the following error:
11:24:49 **** Incremental Build of configuration Debug for project Test ****
Info: Internal Builder is used for build
g++ -o Test.exe hello.o practice.o "-lC:\\C++\\cccfiles"
c:/mingw/bin/../lib/gcc/x86_64-w64-mingw32/5.2.0/../../../../x86_64 w64-mingw32/bin/ld.exe: cannot find -lC:\C++\cccfiles
collect2.exe: error: ld returned 1 exit status
11:24:49 Build Finished (took 777ms)
I've googled every possible thing I could think of for the last two days and nothing has helped me.
I just installed Eclipse on my new PC (using Mint 17.1) and run into this error with almost every Project so far. The problem is that when I want to launch my project I get the error:
"Launch Failed. Binary not found."
I already tried to Build the project but then I get 2 errors:
./src/main.o: undefined reference to symbol 'glEnable'
make: *** [OpenGL] Fehler 1
Here is the console log:
01:49:45 **** Incremental Build of configuration Debug for project OpenGL ****
make all
Building target: OpenGL
Invoking: GCC C++ Linker
g++ -L/usr/lib/ -L/usr/lib/x86_64-linux-gnu/mesa/ -o "OpenGL" ./src/main.o -lglut -lGLU
/usr/bin/ld: ./src/main.o: undefined reference to symbol 'glEnable'
//usr/lib/x86_64-linux-gnu/mesa/libGL.so.1: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make: *** [OpenGL] Fehler 1
01:49:45 Build Finished (took 127ms)
I already searched the web for solutions but I can't seem to find a solution that works.
Based on your error log, you haven't linked -lGL. Try adding it to your libraries in the Linker Settings
I'm trying to get started with SDL and trying to compile a 'hello world' starter app to check my configuration and I get this error:
C:/MinGW-4.8.1/bin/g++.exe -c "C:/Users/Me/Documents/Cpp_Projects/Demo_Graphics/main.cpp" -g -O0 -Wall -o ./Debug/main.cpp.o -I. -IC:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/include
C:/MinGW-4.8.1/bin/g++.exe -o ./Debug/Demo_Graphics #"Demo_Graphics.txt" -L. -lC:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/
c:/mingw-4.8.1/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: cannot find -lC:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/
collect2.exe: error: ld returned 1 exit status
mingw32-make.exe[1]: *** [Debug/Demo_Graphics] Error 1
Demo_Graphics.mk:79: recipe for target 'Debug/Demo_Graphics' failed
mingw32-make.exe[1]: Leaving directory 'C:/Users/Me/Documents/Cpp_Projects/Demo_Graphics'
mingw32-make.exe: *** [All] Error 2
Makefile:4: recipe for target 'All' failed
1 errors, 0 warnings
The directory C:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/ certainly does exist and has the required SDL libraries in it, but I have no clue about compilers.
This is predefined code which should work so the problem is in set up somewhere?
The -l compiler flag is adding a library dependency. It does not specify a path in which to look for libraries (that is the -L flag), which appears to be what you are expecting.
In your error message:
-L. -lC:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/
You can see that the compiler is looking in your current working directory (.) for the library C:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/, but this is not a library -- this is the directory in which you're storing the SDL libraries.
In the CodeLite linker setup you want to change your library path to C:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/, or use
-LC:/Users/Me/Documents/Cpp_Projects/SDL2/32bit/lib/
as a build flag.
You also need to link to the SDL2 library, so you'll need to add -lSDL2 (possibly -lSDL2main as well, I can't remember the specifics of the SDL libraries) to your build/linker flags.
I am trying to learn the CPPUNIT i looked at the following link:
CPPUNIT
although the selected language here is c i have selected c++ while creating this application and have added the
C:\cppunit\cppunit-1.12.1\include to the include directories i have also added cppunitd,cppunit in the linker options however i still the errors as while i try to test the cppunit.
Errors:
c:/mingw/bin/../lib/gcc/mingw32/4.6.1/../../../../mingw32/bin/ld.exe: cannot find
-lcppunitd
c:/mingw/bin/../lib/gcc/mingw32/4.6.1/../../../../mingw32/bin/ld.exe: cannot find -lcppunit
c:/mingw/bin/../lib/gcc/mingw32/4.6.1/../../../../mingw32/bin/ld.exe: cannot find -lcppunit
collect2: ld returned 1 exit status
make[1]: *** [build/Debug/MinGW_1-Windows/tests/TestFiles/f1] Error 1
make: *** [.build-tests-impl] Error 2
BUILD TESTS FAILED (exit value 2, total time: 4s)
Need to use the -L flag and have a path to the library.
I experienced the same linker error and found that I only had 64-bit version of CppUnit installed while building 32-bit application. I solved it by installing 32-bit version of the library.
I'm cross compiling to an arm embedded system and receiving an error that I have questions about. Here is the error:
[ 19%] Built target cxjpeg-6b
Linking CXX shared library /home/botbear/JAUS++-2.110519- src/libraries/jaus++/2.0/lib/libcxutils.so
/home/botbear/openwrt/trunk/staging_dir/toolchain-arm_v6k_gcc-linaro_uClibc- 0.9.32_eabi/lib/gcc/arm-openwrt-linux-uclibcgnueabi/4.5.4/../../../../arm-openwrt-linux- uclibcgnueabi/bin/ld: cannot find -lpng
collect2: ld returned 1 exit status
make[2]: *** [/home/botbear/JAUS++-2.110519-src/libraries/jaus++/2.0/lib/libcxutils.so] Error 1
make[1]: *** [libcxutils/CxUtils/libcxutils/CMakeFiles/cxutils.dir/all] Error 2
make: *** [all] Error 2
As you can see the linker is looking for a static library named 'libpng'. In addition to the libpng lib., the command in the sub-make file using the -l switch to link to the following libraries: -lpng -lz -lX11 -lXtst -lpthread -Wl. All of the libraries (libpng,libz,libX11, etc) are in my host /usr/lib/ directory but my target toolchain does not have the the libraries. My question is if I manually recompile the libraries with my target compiler will that solved my problem? Or I'm going to have find and install packages for each of the libraries for my target platform.
Thanks in advance.
You seem to compile for the target, so you need target libraries. Either compiled by yourself or provided by the toolchain development environment (if you have one). The latter usually saves you some headaches (cross compiling and setting the paths where necessary).
I see you are using openwrt toolchain. Openwrt seems to have libpng as a package. I'd go with that if possible.