view docs/manual/x229.html @ 577:e49d24f4a9a5

Correct bug in the object file output code leading to stack corruption It turns out leaving a pointer to a stack allocated temporary in a persistent data structure is not conducive to correct program operation. Undo the export check setup in the object file output sequence so a pointer to stack allocated memory is not left hanging when the function returns. This seems to correct at least one mysterious crash bug, and possibly others. Thanks to Boisy Pitre for reporting the crash bug that led to this discovery, as well as a previous crash bug that likely has the same root cause. Additional thanks to Ciaran Anscomb whose debugger wielding wizardry revealed the exact location of this particular bit of unbrilliance.
author William Astle <lost@l-w.ca>
date Sat, 03 Aug 2024 14:30:06 -0600
parents 8c6c3363e18e
children
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> LWASM supports all documented MC6809 instructions as defined by
Motorola.  By default, this does not include any MC6800 compatibility
instructions.  As of LWASM 4.11, those compatibility instructions can be
enabled using the <CODE
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> option or the
<CODE
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> pragma.  It also supports all known HD6309
instructions.  While there is general agreement on the mnemonics for most
of the 6309 instructions, there is some variance with the block transfer
instructions.  TFM for all four variations seems to have gained the most
traction and, thus, this is the form that is recommended for LWASM. 
However, it also supports COPY, COPY-, IMP, EXP, TFRP, TFRM, TFRS, and TFRR. 
It further adds COPY+ as a synomym for COPY, IMPLODE for IMP, and EXPAND for
EXP.  </P
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>By default, LWASM accepts 6309 instructions. However, using the
<CODE
CLASS="PARAMETER"
>--6809</CODE
> parameter, you can cause it to throw errors on
6309 instructions instead.</P
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>The standard addressing mode specifiers are supported. These are the
hash sign ("#") for immediate mode, the less than sign ("&lt;") for forced
eight bit modes, and the greater than sign ("&gt;") for forced sixteen bit modes.</P
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>Additionally, LWASM supports using the asterisk ("*") to indicate
base page addressing. This should not be used in hand-written source code,
however, because it is non-standard and may or may not be present in future
versions of LWASM.</P
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