Example compile and link

@c man begin SYNOPSIS gm2 gm2 [@option{-c}|@option{-S}] [@option{-g}] [@option{-pg}]

[@option{-O}@var{level}] [@option{-W}@var{warn}…] [@option{-I}@var{dir}…] [@option{-L}@var{dir}…] [@option{-f}@var{option}…] [@option{-m}@var{machine-option}…] [@option{-o} @var{outfile}] [@@@var{file}] @var{infile}…

Only the most useful options are listed here; see below for the remainder. @c man end @c man begin SEEALSO gpl(7), gfdl(7), fsf-funding(7), gcc(1) and the Info entries for @file{gm2} and @file{gcc}. @c man end The gm2 command is the GNU compiler for the Modula-2 language and supports many of the same options as gcc. See Option Summary. This manual only documents the options specific to gm2.

This section describes how to compile and link a simple hello world program. It provides a few examples of using the different options mentioned in see Compiler options. Assuming that you have a file called hello.mod in your current directory which contains:

MODULE hello ;

FROM StrIO IMPORT WriteString, WriteLn ;

BEGIN
   WriteString('hello world') ; WriteLn
END hello.

You can compile and link it by: gm2 -g hello.mod. The result will be an a.out file created in your directory.

You can split this command into two steps if you prefer. The compile step can be achieved by: gm2 -g -c -fscaffold-main hello.mod and the link via: gm2 -g hello.o.

To see all the compile actions taken by gm2 users can also add the -v flag at the command line, for example:

gm2 -v -g -I. hello.mod

This displays the subprocesses initiated by gm2 which can be useful when trouble shooting.