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<h3 class="section">6.21 Slightly Looser Rules for Escaped Newlines</h3>
<p><a name="index-escaped-newlines-3002"></a><a name="index-newlines-_0028escaped_0029-3003"></a>
The preprocessor treatment of escaped newlines is more relaxed
than that specified by the C90 standard, which requires the newline
to immediately follow a backslash.
GCC's implementation allows whitespace in the form
of spaces, horizontal and vertical tabs, and form feeds between the
backslash and the subsequent newline. The preprocessor issues a
warning, but treats it as a valid escaped newline and combines the two
lines to form a single logical line. This works within comments and
tokens, as well as between tokens. Comments are <em>not</em> treated as
whitespace for the purposes of this relaxation, since they have not
yet been replaced with spaces.
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