Intel XENIX 286 Programmers Guide (86) - Tenox.tc

CHAPTER 3
lint: C PROGRAM CHEC KER
This chapter explains how to use the C program checker lint. The program examines C
source files and warns of errors or misconstructions that may cause errors during
compilation of the file or during execution of the compiled file.
In particular, lint checks for
• Unused functions and variables
• Unknown values in local variables
• Unreachable statements and infinite loops
• Unused and misused return values
• Inconsistent types and type casts
• Mismatched types in assignments
• Nonportable and old-fashioned syntax
• Strange constructions
• Inconsistent pointer alignment and expression evaluation order
The lint program and the C compiler are generally used together to check and compile C
language programs. Although the C compiler rapidly and efficiently compiles C
language source files, it does not perform the sophisticated type and error checking
required by many programs. The lint program, on the other hand, provides thorough
checking of source files without compiling.
Invoking lint
You can invoke lint by typing its name at the shell command prompt. The command has
the form
lint [ option ] ... filename ... lib ...
where option is a command option that defines how the checker should operate,
filename is the name of a C language source file to be checked, and lib is the name of a
library to check. You can give more than one option, file name, or library name in the
command as long as you use spaces to separate them. If you give two or more file
names, lint assumes that the files form a complete program and checks the 'files
accordingly. For example, the command
lint main.c add.c
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