view docs/manual/x187.html @ 273:1409debcb1a0

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
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>3.4. Symbols</A
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>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
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>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
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>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
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