I am trying to compile an FLTK program (http://www.fltk.org/index.php) on Mac OSX Mavericks. All the .h packages compile just fine, but I receive the following error:
ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) I tried both g++ and clang++ -stdlib=libstdc++ to compile the program, but received the same error both times.
I would greatly appreciate any input on this issue to eliminate this error message.
You want to use the fltk-config script but it isn't clear how to use it generally form their documentation. This is a general form that I use and what it is actually doing:
From the command line you can compile like this (this assumes you need the image libraries, opengl libraries and wish to link statically [half the point of FLTK])
g++ file1.cpp file2.cpp `fltk-config --use-forms --use-gl --use-images --ldstaticflags --cxxflags` -o output This is equivalent to
g++ file1.cpp file2.cpp -I/usr/local/include -I/usr/local/include/FL/images -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_THREAD_SAFE -D_REENTRANT /usr/local/lib/libfltk_images.a /usr/local/lib/libfltk_png.a -lz /usr/local/lib/libfltk_jpeg.a /usr/local/lib/libfltk_gl.a -framework AGL -framework OpenGL -framework ApplicationServices /usr/local/lib/libfltk_forms.a /usr/local/lib/libfltk.a -lpthread -framework Cocoa -o output So if you make sure the libraries are in /usr/local/lib and the headers in /usr/local/include that should work...
fltk-config is just a script that comes in the fltk-1.3.2 (or whatever) folder. Building FLTK from the make file should add that to your path. If not copy it or direct it to wherever it is. It does make me wonder though: have you definitely built the libraries?
-bash: fltk-config: command not found working properly? The command that I'm using is g++ /path/to/file.cxx -I/path/to/fltk-1.3.2 $(fltk-config --ldflags)
make all etc. etc. and built the libraries?fltk-config should be in /usr/local/bin, the FL/ and GL/ directories in usr/local/include and you should have libraries like fltk.a in usr/local/lib. IF not something has gone wrong with your build. Don't try to use the compiler link facility to reach fltk-config. Either copy it to your pwd or copy it to your path (or /usr/local/bin).find / -name "fltk-config" 2> /dev/null I came up with nothing, but when I do find / -name "fltk-config.in" 2> /dev/null I come up with the place where to find fltk-config.in, which is a Unix executable file. Then when I type: g++ /path/to/fltk-1.3.3/file.cxx -I /path/to/fltk-1.3.3 /path/to/fltk-1.3.3/fltk-config.in --ldflags I get the error clang: error: unsupported option '--ldflags'fltk-1.3.2 type ./configure --enable-threads with any other options you need (See documentation) then sudo make installThis is what worked for me:
#!/bin/bash rm ./a.out clang++ main.cpp -o a.out -std=c++17 -stdlib=libc++ \ -I/usr/include/fltk-1.3.8/FL \ -L/usr/local/lib \ $(fltk-config --ldflags) \ && ./a.out 
brew install fltk fltk-config --compile ./example_file.cpp ./example_file 
g++ /path/to/file.cxx -I/path/to/fltk-1.3.2and also triedclang++ -stdlib=libstdc++ /path/to/file.cxx -I/path/to/fltk-1.3.2both of which gave the same error. I used the -I flag as shown here under the "Compiling programs with standard compilers" section: fltk.org/doc-1.1/basics.html$(fltk-config --ldflags)$()and run that stand-alone to see what it gives for linker flags too.-bash: fltk-config: command not found. Any suggestions?