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



   <p>A <dfn>statement</dfn> ends at a newline character (<code>\n</code>) or line

separator character.  (The line separator is usually <code>;</code>, unless

this conflicts with the comment character; see <a href="Machine-Dependencies.html#Machine%20Dependencies">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>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 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 <code>.</code> 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 <code>as</code> 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 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, ...

     </pre>



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