I have a C-code which I have not managed to run
http://dl.getdropbox.com/u/175564/problem-sdl.png
The problem is in OpenGL or SDL.
I do not have SDL.h at /usr/local/SDL/SDL.h, so gcc cannot find it.
I have SDL.h installed by MacPorts at /opt/local/include/SDL/SDL.h.
I tried to copy it to /Masi/local/SDL/SDL.h unsuccessfully at the folder by
cp /opt/local/include/SDL/SDL.h /
and by
cp /opt/local/include/SDL/SDL.h /Masi/local/SDL/
I tried to solve the problem by creationg a symlink by
$ln -s /opt/local/include/SDL/SDL.h /Masi/local/SDL/SDL.h
the simplest way to get all the compiler flags for SDL is by using sdl-config:
gcc sdl_gl_1.c $(sdl-config --cflags --libs) -lGL -lGLU
No, Ubuntu does not have them by default (at least the development versions). For my own little program I just installed libsdl1.2-dev and mesa-common-dev (OpenGL).
For the build process I use scons which produces the following commands:
gcc -o src/geom.o -c -Wall -ansi src/geom.c
gcc -o src/main.o -c -Wall -ansi src/main.c
gcc -o test src/main.o src/geom.o -lSDL -lGL
If you install the libraries in some non-standard location, you might have to specify your own include (-I) and library (-L) paths.
Related
So recently I downloaded the Linux Subsystem on Windows 10, with Ubuntu.
I can compile an SDL2 app to Linux with the g++ command but whenever I try doing it with i686-w64-mingw32-g++ this command, I get an error saying main.cpp:5:9: fatal error: SDL2/SDL.h: No such file or directory.
The command I'm using is i686-w64-mingw32-g++ main.cpp -w -lSDL2 -o main.exe.
https://imgur.com/a/uqcGCoJ
Anyone knows how to fix this? :(
[EDIT]
So now I've tried specifying the directory of the necesary files with this command: g++ main.cpp -I/usr/include/SDL -L/usr/lib/x86_64-linux-gnu -w -Wall -Wextra -std=c++17 -lSDL2 -o main
which worked but when I use it with mingw it doesn't i686-w64-mingw32-g++ main.cpp -I/usr/include/SDL -L/usr/lib/x86_64-linux-gnu -w -Wall -Wextra -std=c++17 -lSDL2 -o main
https://imgur.com/a/sF6CpcP
You need to include the path to SDL's include directory on the command line. However, you need to include the path to the downloaded SDL for mingw32, not /usr/include/SDL2. The difference is the headers in /usr/include/SDL2 are for Linux and libs in /usr/lib are also for Linux, but you need to link to the Windows libraries.
What I usually do is download the development libraries for Mingw32 and put them directly into my project directory. Then all you need to do is add -ISDL2-2.0.8/i686-w64-mingw32/include -LSDL2-2.0.8/i686-w64-mingw32/lib to your command line and it will be able to find the headers and libraries it needs. Finally, make sure you copy SDL2-2.0.8/i686-w64-mingw32/bin/SDL2.dll to your executable directory in the Makefile.
Also, remember to link SDLmain as well. It handles creating a WinMain for you and all that, and then calls your main function.
I'm trying to compile statically my C++ project on Redhat 7.3.
This is my script:
g++ -static -ldl -std=c++0x -O3 -fopenmp *.cpp -o main
But I obtain this error: /usr/bin/ld: cannot find -ldl
How can I fix it?
I think a library misses.
-ldl means /usr/lib/libdl.so
( Provided by glibc-devel )
the -static -ldl means /usr/lib/libdl.a
( Provided by glibc-static )
yum install glibc-devel glibc-static
I'm trying to experiment around in ncurses for the first time, but I'm having problems compiling my source code. As far as I can tell, ncurses is installed and in the proper directories.
My makefile is super simple:
.cpp :
g++ -Wall -g -o $* $*.cpp -std=c++11 -lncurses
and here's my output when I try to locate ncurses.h
$ locate ncurses.h
/usr/include/ncursesw/ncurses.h
and when I check to see if it's installed
$ dpkg -l | grep ncurses
ii libncurses5:amd64 5.9+20140118-1ubuntu1 amd64 shared libraries for terminal handling
ii libncursesw5:amd64 5.9+20140118-1ubuntu1 amd64 shared libraries for terminal handling (wide character support)
ii libncursesw5-dev:amd64 5.9+20140118-1ubuntu1 amd64 developer's libraries for ncursesw
ii mtr-tiny 0.85-2 amd64 Full screen ncurses traceroute tool
ii ncurses-base 5.9+20140118-1ubuntu1 all basic terminal type definitions
ii ncurses-bin 5.9+20140118-1ubuntu1 amd64 terminal-related programs and man pages
ii ncurses-term 5.9+20140118-1ubuntu1 all additional terminal type definitions
But g++ tells me this when I try to make
bankacct.cpp:18:29: fatal error: ncurses.h: No such file or directory
compilation terminated.
Unfortunately, I've not got root access and I need to be able to compile on this machine. What are my options?
I've tried including <ncursesw/ncurses.h> based on suggestions from other users, but now g++ is giving me this error:
$ make bankacct
g++ -Wall -g -o bankacct bankacct.cpp -std=c++11 -lncurses
/usr/bin/ld: cannot find -lncurses
and if I try removing -lncurses it gives me this:
$ make bankacct
g++ -Wall -g -o bankacct bankacct.cpp -std=c++11
/tmp/cc8rPQfK.o: In function `main':
bankacct.cpp:23: undefined reference to `initscr'
Now I've tried linking the libraries. Here's what I did:
$ locate libncurse
/lib/x86_64-linux-gnu/libncurses.so.5
/lib/x86_64-linux-gnu/libncurses.so.5.9
/lib/x86_64-linux-gnu/libncursesw.so.5
/lib/x86_64-linux-gnu/libncursesw.so.5.9
/usr/lib/x86_64-linux-gnu/libncurses++w.a
/usr/lib/x86_64-linux-gnu/libncursesw.a
/usr/lib/x86_64-linux-gnu/libncursesw.so
/usr/share/doc/libncurses5
/usr/share/doc/libncursesw5
/usr/share/doc/libncursesw5-dev
/var/lib/dpkg/info/libncurses5:amd64.list
/var/lib/dpkg/info/libncurses5:amd64.md5sums
/var/lib/dpkg/info/libncurses5:amd64.postinst
/var/lib/dpkg/info/libncurses5:amd64.postrm
/var/lib/dpkg/info/libncurses5:amd64.shlibs
/var/lib/dpkg/info/libncurses5:amd64.symbols
/var/lib/dpkg/info/libncursesw5-dev:amd64.list
/var/lib/dpkg/info/libncursesw5-dev:amd64.md5sums
/var/lib/dpkg/info/libncursesw5-dev:amd64.postinst
/var/lib/dpkg/info/libncursesw5:amd64.list
/var/lib/dpkg/info/libncursesw5:amd64.md5sums
/var/lib/dpkg/info/libncursesw5:amd64.postinst
/var/lib/dpkg/info/libncursesw5:amd64.postrm
/var/lib/dpkg/info/libncursesw5:amd64.shlibs
/var/lib/dpkg/info/libncursesw5:amd64.symbols
So then I tried two variations of my makefile:
g++ -Wall -g -L/usr/lib/x86_64-linux-gnu/ -o $* $*.cpp -std=c++11 -lncurses
and
g++ -Wall -g -L/lib/x86_64-linux-gnu/ -o $* $*.cpp -std=c++11 -lncurses
which still gave me the errors undefined reference to 'initscr' (without -lncurses) or /usr/bin/ld: cannot find -lncurses (with it)
-lncurses
tells the linker to look for a library called "ncurses.". You clearly indicate that's not what your library is called:
/usr/lib/x86_64-linux-gnu/libncursesw.a
You need
-lncursesw
You don't need to modify the source code to specify <ncursesw/ncurses.h> you can simply add
-I/usr/include/ncursesw
I'm trying to compile the simavr project from https://github.com/buserror/simavr on Windows 10 using MSYS2 and mingw-w64.
After editing the makefiles to enable the MSYS clauses (Which are commented out by default), and changing the order of 2 include files, I can get the project to compile. I do however encounter an error in the linking step.
The output is
C:/Programs/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/5.3.0/../../../../i686-w64-mingw32/bin/ld.exe: cannot find -lsimavr
Editing the makefile to print the ${LDFLAGS}, yield the following.
-L/lib -L/local/lib -L/c/Users/University/GitHub/simavr/simavr/../simavr/obj-i686-w64-mingw32 -lsimavr -lelf -lws2_32
Looking in the folder "obj-i686-w64-mingw32" mentioned in the build script, the file "libsimavr.a" is present. If I copy the file to the msys lib folder the linking step works fine.
The folder structure of the project is as follows:
simavr root (Where i run the makefile from, located in /c/Users/University/GitHub)
simavr
obj-i686-w64-mingw32
As far as I can tell, LD should be able to link properly without me copying the file manually. What am I missing here?
Edit:
The final command before the linker error.
cc -MMD -Werror -O2 -Wall -g -I/usr/local/include -DNO_COLOR -o obj-i686-w64-mingw32/run_avr.elf obj-i686-w64-mingw32/run_avr.o -L/lib -L/local/lib -L/c/Users/University/GitHub/simavr/simavr/../simavr/obj-i686-w64-mingw32 -lsimavr -lelf -lws2_32
Edit 2:
Cleaning the include paths of MSYS folders:
cc -MMD -Werror -O2 -Wall -g -DNO_COLOR -o obj-i686-w64-mingw32/run_avr.elf obj-i686-w64-mingw32/run_avr.o -L/c/Users/University/GitHub/simavr/simavr/../simavr/obj-i686-w64-mingw32 -lsimavr -lelf -lws2_32
C:/Programs/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/5.3.0/../../../../i686-w64-mingw32/bin/ld.exe: cannot find -lsimavr
Passing CC=gcc to make:
gcc -MMD -Werror -O2 -Wall -g -DNO_COLOR -o obj-i686-w64-mingw32/run_avr.elf obj-i686-w64-mingw32/run_avr.o -L/c/Users/University/GitHub/simavr/simavr/../simavr/obj-i686-w64-mingw32 -lsimavr -lelf -lws2_32
C:/Programs/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/5.3.0/../../../../i686-w64-mingw32/bin/ld.exe: cannot find -lsimavr
Edit 3:
Output of the find command:
$ find /c/Users/University/GitHub/simavr -name 'libsimavr.a'
/c/Users/University/GitHub/simavr/simavr/obj-i686-w64-mingw32/libsimavr.a
Note that previous entries have been made using the git bash prompt, not the one from msys2. However, running the same commands in the msys2 prompt or the mingw prompt from msys2 yields the same results.
Using mingw-w64 toolchain to build project you MUST remove from CFLAGS/CXXFLAGS/CPPFLAGS all paths with /usr, /local, /lib, /include as this paths can contain headers and libs from MSYS2 itself. Second, try pass "CC=gcc" to makefile.
I've been trying to go through Boost tutorials but I got stuck at linking the filesystem library.
I have Ubuntu 12.10. Installation wasn't that hard
sudo apt-get install libboost-all-dev
This put all headers in /usr/local/include and compiled sources in /usr/lib/
[--headers]
[--binaries]
I wrote this program [--program]. When I tried to compiled it
g++ -g tut1.cpp -o tut1 -lboost_system -lboost_filesystem
got this errors: [--errors].
After a little search on http://www.boost.org/doc/libs/1_53_0/more/getting_started/unix-variants.html
I tried this:
g++ -g -I /usr/local/include/boost/ tut1.cpp -o tut1 -L /usr/lib/libboost_filesystem.a -lboost_system -lboost_filesystem
but didn't have luck. I had the same errors.
Since I cannot put more than 2 links in the post, here are all links
http://pastebin.com/DakVFn12
I found the answer myself here:
http://www.richelbilderbeek.nl/CppLinkErrorUndefinedReferenceToBoostFilesystemDetailGet_current_path_api.htm
Looks like binaries weren't in /usr/lib but in /usr/local/lib.
So the correct command for compilation would be:
g++ -g tut1.cpp -o tut1 -L/usr/local/lib/ -lboost_filesystem
#Yuushi, that was 1 problem.
The -L command should be the base path where the libraries are contained, not the path to a specific library. Try with -L /usr/lib/ instead.