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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I noticed something strange when I use the “native”
option to compile my code. Code reloading doesn’t work the same way as
when I don’t specify “native”. Here’s some sample
code.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>-module(reload).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>-export([show/0, loop/0, version/0]).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>show() -> spawn(fun loop/0).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>loop() -><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> io:format("This process: ~p, Most current
version: ~p ~n",<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> [version(), reload:version()]),<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> receive<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> reload -> reload:loop();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> exit -> void<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> after 5000 -><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> loop()<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> end.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>%% Change this each time:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>version() -> 22.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>When I don’t use the native mode, it works as documented.
When I change the version number and say “c(reload)” the first
version number stays the same and the second version number is incremented.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If I say “c(reload, native)” then it acts
strange. In that case both version numbers change to the latest one. More
precisely:<o:p></o:p></span></font></p>
<ul style='margin-top:0in' type=disc>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>The recursive call to loop()
always calls the original version of the code, as it should. (Change the
io:format statement if you want to verify that.)<o:p></o:p></span></font></li>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>The recursive call to
reload:loop() always calls the most recent version of the code, as it
should.<o:p></o:p></span></font></li>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>The call to reload:version()
always calls the most recent version of the code, as it should.<o:p></o:p></span></font></li>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>The call to version() works
differently in different cases. If you compiled without the native
switch, it calls the original version of the code, as it should. If you
compiled with the native switch, it incorrectly calls the latest version.<o:p></o:p></span></font></li>
</ul>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I noticed something else that was strange, although I’m
not sure if it’s a bug or a feature. When I don’t use the “native”
switch, I can see that there are only two versions of the code. Erlang kills
my process if it’s using code that’s too old, exactly as
documented. However, if I compile with the “native” switch then Erlang
never kills my old code.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m running otp_src_R11B-5.tar.gz on Fedora.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>PS The native option makes things work much faster!<o:p></o:p></span></font></p>
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