Using the GNU C++ Compiler¶

Overview¶

The GNU Compiler Collection (GCC) is an integrated collection of compilers for several languages, including C, C++, Java and Fortran.

Our interest here is with the C/C++ compiler.

Syntax¶

The g++ command has the following syntax:


g++ [-option...] file... [option	file]...

where option denotes an option or switch (see below) and file denotes a file name.

Options¶

The list of valid options/switches for the g++ command includes the following:

Option	Purpose
c	Compiles without linking
Dname=definition	Defines a symbol (as with `#define`)
E	Stop after the preprocessing stage
g	Produce debugging information
I	Searches the given directory for "includes"
llibname	Searches the specified library when linking
ofilename	Names the output file
M	Instead of preprocessing, output a rule suitable for use by `make`
-help	Provides (some) help
-version	Displays the version number

Examples¶

The following command compiles (but does not link) the C source file named test.c and creates the file test.o:

g++ -c test.c

The following command first defines the symbol DEBUG in the C++ source file named Demo.cpp and then compiles and links it (creating an executable file named Demo).

g++ -DDEBUG=VERBOSE Demo.cpp -o Demo

The following command "includes" files from the directory /myfiles/include in addition to the standard INCLUDE directory.

g++ -I/myfiles/include Demo.cpp -o Demo

The following commands first compile the source files for a small application (written in C) and then links them into an executable named example.

g++ -c account.c
g++ -c example.c
g++ example.o account.o -o example

Error and Warning Messages¶

Error and warning messages generated by the GCC are often less than clear. There are several places you can go for help, including:

Compiler Error Messages (courtesy of Network Theory, Ltd.)
Common Error Messages (courtesy of California Polytechnic State University)

Last modified: 2018-08-10 15:54 by David Bernstein (eea3f52)