C++¶
Compilation¶
The default compiler is GCC which includes the gcc program for C and g++ for C++.
If necessary, you can load the gcc module to have a different version from the one included with the system. For example:
module load gcc
It is possible that these version might have unforeseen problems in some circumstances so we recommend that you stick to the default compiler.
Compilation options¶
| Option | Description |
|---|---|
-O |
Optimiser the program. |
-g |
Debug the program |
-Wall |
Get more warning when compiling. |
-o program_name |
Name of the program we want to create |
-c |
To create only the object files (.o) |
-I dir |
Add non standard include direcrory |
-L dir |
Add non standard library directory |
-lname |
Link with a library |
Examples¶
If your program is contained in a single file, you can use this command to build an optimized program.
gcc -O -Wall -o hello hello.c
If you need to debug the program, replace -O with -g.
If your program has more than one file, usually objects files are created first and then they are linked together. It's what is done in most Makefile.
gcc -O -Wall -c hello1.c
gcc -O -Wall -c hello2.c
gcc -O -o hello hello1.o hello2.o
As you can see, we're using the -c option to compile a .c to an object file .o.
If you have a C++ program, replace gcc by g++
g++ -O -Wall -c hello1.c
g++ -O -Wall -c hello2.c
g++ -O -o hello hello1.o hello2.o
Compile a program with the cplex library.
gcc -O -Wall -DNDEBUG -DIL_STD -c lpex1.c
gcc -O -o lpex1 lpex1.o -lcplex -lm -lpthread
Compile a C++ program with cplex and concert.
g++ -O -Wall -DNDEBUG -DIL_STD -c cutstock.cpp
g++ -O -o cutstock cutstock.o -lilocplex -lconcert -lcplex -lm -lpthread
Compile a C++ program using gurobi
module load gurobi
g++ -o sudoku sudoku_c++.cpp -lgurobi_g++5.2 -lgurobi100