3392664 – "mov al, byte [edx]" does not cause error when "cpu 8086" is in effect

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Bug 3392664 - "mov al, byte [edx]" does not cause error when "cpu 8086" is in effect

Summary: "mov al, byte [edx]" does not cause error when "cpu 8086" is in effect

Status:	OPEN

Alias:	None

Product:	NASM
Classification:	Unclassified
Component:	Assembler (show other bugs)
Version:	2.15.xx
Hardware:	All All

Importance:	Low normal
Assignee:	nobody

URL:

Depends on:
Blocks:

Reported:	2020-05-20 04:56 PDT by E. C. Masloch
Modified:	2020-05-24 17:06 PDT (History)
CC List:	4 users (show)

Obtained from:	Built from git using configure
Generated by:	---
Bug category:
Observed for:	---
Regression:	---
Regression since:

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Description E. C. Masloch 2020-05-20 04:56:27 PDT

$ cat test2.asm
cpu 8086
mov al, byte [edx]
$ nasm -v
NASM version 2.15rc0 compiled on Nov 22 2019
$ nasm test2.asm -l /dev/stderr -o test2.bin
     1                                  cpu 8086
     2 00000000 678A02                  mov al, byte [edx]
$

Comment 1 H. Peter Anvin 2020-05-24 17:06:39 PDT

Unfortunately, the CPU directives are not well implemented in NASM and need a lot more work. At this point, their main purpose is to handle the cases where it has to generate different code for different CPUs, e.g. jump-overs for long conditional jumps. It is not at all ideal, but unless someone steps up to enhance it, it is unlikely to change.