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

XENIX Programming cc: C Compiler
You can avoid many C compiler errors by using the XENIX C program checker lint
before compiling your C source files. lint performs detailed error checking on a source
file and provides a list of actual errors and possible problems that may affect execution
of the program. For a description of lint, see Chapter 3, "lint: C Program Checker."
Setting the Level of Warnings
You can set the level of warning messages produced by the compiler by using the -W
option. This option directs the compiler to display messages about statements that may
not be compiled as the programmer intends. Warnings indicate potential problems
rather than actual errors. The option has the form
-W number
where number is a number in the range 0 to 3 giving the level of warnings. The levels
are
0 Suppresses all warning messages. Only messages about actual syntactic or
semantic errors are displayed.
1 Warns about potentially missing statements, unreachable statements, and
other structural problems. Also warns about overt type mismatches.
2 Warns about all type mismatches (strong typing).
3 Warns on all automatic data conversions.
If the option is not used, the default is level 1.
The higher option levels are especially useful in the earlier stages of program
development when messages about potential problems are most helpful. The lower
levels are best for compiling programs whose questionable statements are intentionally
designed. For example, the command
cc -W 3 mai n.c
directs the compiler to perform the highest level of checking and produces the greatest
number of warning messages. The command
cc -W 0 · main.c
produces no warning messages. Note that the -w option has the same effect as -W 0.
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