The warnings that can be given by
troff are divided into the following categories. The name associated with each warning is used by the
-w and
-W options; the number is used by the
warn request, and by the
.warn register; it is always a power of 2 to allow bitwise composition.
tab(@), center, box; c c c | c c c r rI lB | r rI lB. Bit@Code@Warning@Bit@Code@Warning _ 0@1@char@10@1024@reg 1@2@number@11@2048@tab 2@4@break@12@4096@right-brace 3@8@delim@13@8192@missing 4@16@el@14@16384@input 5@32@scale@15@32768@escape 6@64@range@16@65536@space 7@128@syntax@17@131072@font 8@256@di@18@262144@ig 9@512@mac@19@524288@color
nxu+3n breakt4
In fill mode, lines which could not be broken so that their length was less than the line length. This is enabled by default.
chart1
Non-existent characters. This is enabled by default.
colort524288
Color related warnings.
delimt8
Missing or mismatched closing delimiters.
dit256
Use of di or da without an argument when there is no current diversion.
elt16
Use of the el request with no matching ie request.
escapet32768
Unrecognized escape sequences. When an unrecognized escape sequence is encountered, the escape character is ignored.
fontt131072
Non-existent fonts. This is enabled by default.
igt262144
Invalid escapes in text ignored with the ig request. These are conditions that are errors when they do not occur in ignored text.
inputt16384
Invalid input characters.
mact512
Use of undefined strings, macros and diversions. When an undefined string, macro or diversion is used, that string is automatically defined as empty. So, in most cases, at most one warning will be given for each name.
missingt8192
Requests that are missing non-optional arguments.
numbert2
Invalid numeric expressions. This is enabled by default.
ranget64
Out of range arguments.
regt1024
Use of undefined number registers. When an undefined number register is used, that register is automatically defined to have a value of 0. So, in most cases, at most one warning will be given for use of a particular name.
right-bracet4096
Use of \} where a number was expected.
scalet32
Meaningless scaling indicators.
spacet65536
Missing space between a request or macro and its argument. This warning will be given when an undefined name longer than two characters is encountered, and the first two characters of the name make a defined name. The request or macro will not be invoked. When this warning is given, no macro is automatically defined. This is enabled by default. This warning will never occur in compatibility mode.
syntaxt128
Dubious syntax in numeric expressions.
tabt2048
Inappropriate use of a tab character. Either use of a tab character where a number was expected, or use of tab character in an unquoted macro argument.
There are also names that can be used to refer to groups of warnings:
all
All warnings except di, mac, and reg. It is intended that this covers all warnings that are useful with traditional macro packages.