-qformat

Pragma equivalent

None.

Purpose

Warns of possible problems with string input and output format specifications.

Functions diagnosed are printf, scanf, strftime, strfmon family functions and functions marked with format attributes.

Syntax


        .-noformat-----------------------.   
>>- -q--+-format--+--------------------+-+---------------------><
                  |    .-:-----------. |     
                  |    V .-all-----. | |     
                  '-=----+-noall---+-+-'     
                         +-exarg---+         
                         +-noexarg-+         
                         +-nlt-----+         
                         +-nonlt---+         
                         +-sec-----+         
                         +-nosec---+         
                         +-y2k-----+         
                         +-noy2k---+         
                         +-zln-----+         
                         '-nozln---'

Defaults

-qnoformat

Parameters

all | noall: Enables or disables all format diagnostic messages.
exarg | noexarg: Warns if excess arguments appear in printf and scanf style function calls.
nlt | nonlt: Warns if a format string is not a string literal, unless the format function takes its format arguments as a va_list.
sec | nosec: Warns of possible security problems in use of format functions.
y2k | noy2k: Warns of strftime formats that produce a 2-digit year.
zln | nozln: Warns of zero-length formats.

Specifying -qformat with no suboptions is equivalent to -qformat=all.

-qnoformat is equivalent to -qformat=noall.

Predefined macros

None.

Examples

To enable all format string diagnostics, enter either of the following:

xlc myprogram.c -qformat=all

xlc myprogram.c -qformat

To enable all format diagnostic checking except that for y2k date diagnostics, enter:

xlc myprogram.c -qformat=all:noy2k