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Fix crash on listing when nested noexpand macros are used
Macros flagged noexpand were causing a segfault during listing. The problem
was incorrect accounting for nesting levels for noexpand macros causing the
listing handler to fall off the end of the program in certain circumstances
and in other circumstances it would fail to suppress expansion. Both the
segfault in the case of misbehaviour and the misbhaviour itself are
corrected with this update.
If you do not use nested noexpand macros, this bug has no effect.
author | William Astle <lost@l-w.ca> |
---|---|
date | Sat, 25 May 2013 13:35:46 -0600 |
parents | 2cc599f1bebf |
children |
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Symbols</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="LW Tool Chain" HREF="index.html"><LINK REL="UP" TITLE="LWASM" HREF="c45.html"><LINK REL="PREVIOUS" TITLE="Source Format" HREF="x177.html"><LINK REL="NEXT" TITLE="Numbers and Expressions" HREF="x192.html"></HEAD ><BODY CLASS="SECTION" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >LW Tool Chain</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="x177.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 3. LWASM</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="x192.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECTION" ><H1 CLASS="SECTION" ><A NAME="AEN187" >3.4. Symbols</A ></H1 ><P >Symbols have no length restriction. They may contain letters, numbers, dots, dollar signs, and underscores. They must start with a letter, dot, or underscore.</P ><P >LWASM also supports the concept of a local symbol. A local symbol is one which contains either a "?" or a "@", which can appear anywhere in the symbol. The scope of a local symbol is determined by a number of factors. First, each included file gets its own local symbol scope. A blank line will also be considered a local scope barrier. Macros each have their own local symbol scope as well (which has a side effect that you cannot use a local symbol as an argument to a macro). There are other factors as well. In general, a local symbol is restricted to the block of code it is defined within.</P ><P >By default, unless assembling to the os9 target, a "$" in the symbol will also make it local. This can be controlled by the "dollarlocal" and "nodollarlocal" pragmas. In the absence of a pragma to the contrary, for the os9 target, a "$" in the symbol will not make it considered local while for all other targets it will.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="x177.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="x192.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Source Format</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="c45.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Numbers and Expressions</TD ></TR ></TABLE ></DIV ></BODY ></HTML >