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<h3 class="section">3.5 Statements</h3>

<p><a name="index-statements_002c-structure-of-130"></a><a name="index-line-separator-character-131"></a><a name="index-statement-separator-character-132"></a>A <dfn>statement</dfn> ends at a newline character (&lsquo;<samp><span class="samp">\n</span></samp>&rsquo;) or line
separator character.  (The line separator is usually &lsquo;<samp><span class="samp">;</span></samp>&rsquo;, unless this
conflicts with the comment character; see <a href="Machine-Dependencies.html#Machine-Dependencies">Machine Dependencies</a>.)  The
newline or separator character is considered part of the preceding
statement.  Newlines and separators within character constants are an
exception: they do not end statements.

   <p><a name="index-newline_002c-required-at-file-end-133"></a><a name="index-EOF_002c-newline-must-precede-134"></a>It is an error to end any statement with end-of-file:  the last
character of any input file should be a newline.

   <p>An empty statement is allowed, and may include whitespace.  It is ignored.

   <p><a name="index-instructions-and-directives-135"></a><a name="index-directives-and-instructions-136"></a><!-- "key symbol" is not used elsewhere in the document; seems pedantic to -->
<!-- @defn{} it in that case, as was done previously...  doc@cygnus.com, -->
<!-- 13feb91. -->
A statement begins with zero or more labels, optionally followed by a
key symbol which determines what kind of statement it is.  The key
symbol determines the syntax of the rest of the statement.  If the
symbol begins with a dot &lsquo;<samp><span class="samp">.</span></samp>&rsquo; then the statement is an assembler
directive: typically valid for any computer.  If the symbol begins with
a letter the statement is an assembly language <dfn>instruction</dfn>: it
assembles into a machine language instruction. 
Different versions of <samp><span class="command">as</span></samp> for different computers
recognize different instructions.  In fact, the same symbol may
represent a different instruction in a different computer's assembly
language.

   <p><a name="index-g_t_0040code_007b_003a_007d-_0028label_0029-137"></a><a name="index-label-_0028_0040code_007b_003a_007d_0029-138"></a>A label is a symbol immediately followed by a colon (<code>:</code>). 
Whitespace before a label or after a colon is permitted, but you may not
have whitespace between a label's symbol and its colon. See <a href="Labels.html#Labels">Labels</a>.

   <p>For HPPA targets, labels need not be immediately followed by a colon, but
the definition of a label must begin in column zero.  This also implies that
only one label may be defined on each line.

<pre class="smallexample">     label:     .directive    followed by something
     another_label:           # This is an empty statement.
                instruction   operand_1, operand_2, ...
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