...
All occurrences in a source file of the following sequences of three characters (that is, trigraph sequences) are replaced with the corresponding single character.
??=
#
??)
]
??!
|
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="094f0d9205cf7e63-fb7da6ab-43d84cfe-a6b7b5ae-631d7de7047abd63701eeb53"><ac:plain-text-body><![CDATA[
??(
[
??'
^
??>
}
]]></ac:plain-text-body></ac:structured-macro>
??/
\
??<
{
??-
~
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Automated Detection
GCC provides a {{-Wtrigraphs}} option that warns when trigraphs are used. GCC also provides a --no-trigraph option that is enabled by default.
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