<body><div id="__MailbirdStyleContent" style="font-size: 10pt;font-family: Arial;color: #000000">
> <span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px">Why do you think this is the wrong print string?</span><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px">It happens easily to evaluate the printString again. If we now have ModificationForbidden, this can be quite confusing.</span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px">Same for #storeString:</span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif"><span style="font-size: 16px">{1. 2. 3} storeString -> '#(1 2 3)'</span></span><br></div><div><span style="font-family: Calibri, Helvetica, sans-serif"><span style="font-size: 16px"><br></span></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif"><span style="font-size: 16px">Best,</span></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif"><span style="font-size: 16px">Marcel</span></span></div><div class="mb_sig"></div><blockquote class="history_container" type="cite" style="border-left-style:solid;border-width:1px; margin-top:20px; margin-left:0px;padding-left:10px;">
<p style="color: #AAAAAA; margin-top: 10px;">Am 25.03.2020 09:32:04 schrieb Thiede, Christoph <christoph.thiede@student.hpi.uni-potsdam.de>:</p><div style="font-family:Arial,Helvetica,sans-serif">
<div id="divtagdefaultwrapper" style="font-size: 12pt;color: #000000;font-family: Calibri,Helvetica,sans-serif" dir="ltr">
<p>Hi Marcel, hi Levente!</p>
<p><br>
</p>
<p>> <span style="font-size: 12pt">For starters, the #printString of modifiable arrays is wrong if literal arrays should be immutable:</span></p>
<div>> </div>
<div>> x := {1. 2. 3}.</div>
<div>> x at: 1 put: #foo.</div>
<div>> x "#(#foo 2 3) --- wrong print string!"</div>
<div><br>
</div>
<div><span style="font-size: 12pt">Why do you think this is the wrong print string? {#foo. 2. 3} is also printed as #(#foo 2 3).</span><br>
</div>
<div><br>
</div>
<div>Also, the following example shows that brace nodes generate a new instance each time:</div>
<div><br>
</div>
<div>
<div>c := Object newSubclass.</div>
<div>c compile: 'foo ^ {1. 2. 3}'.</div>
<div>o := c new.</div>
<div>o foo at: 1 put: #foo.</div>
<div>o foo. "#(1 2 3)"</div>
<br>
</div>
<div>Best,</div>
<div>Christoph</div>
<p>
<div id="Signature">
<div id="divtagdefaultwrapper" dir="ltr" style="font-size: 12pt;color: rgb(0, 0, 0);font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols">
<div name="divtagdefaultwrapper" style="font-family: Calibri,Arial,Helvetica,sans-serif;font-size: ;margin: 0">
<div><span style="font-size: 10pt;color: #808080"></span></div>
</div>
</div>
</div>
</div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><span style="font-family: Calibri, sans-serif;color: #000000"><b>Von:</b> Squeak-dev <squeak-dev-bounces@lists.squeakfoundation.org> im Auftrag von Taeumel, Marcel<br>
<b>Gesendet:</b> Mittwoch, 25. März 2020 09:19:01<br>
<b>An:</b> gettimothy via Squeak-dev<br>
<b>Betreff:</b> Re: [squeak-dev] Save as new image -> ModificationForbidden!</span>
<div> </div>
</div>
<div>
<div id="__MailbirdStyleContent" style="font-size: 10pt;font-family: Arial;color: #000000">
Hi Levente, hi Christoph.
<div><br>
</div>
<div>> <span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px">I cannot reproduce this using a fresh Trunk image</span></div>
<div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br>
</span></div>
<div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px">I am not exactly sure why my Trunk image keeps generating those private keys. But I am happy that the bug surfaced. Now we need to address it. :-)</span></div>
<div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br>
</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">> The main issue is that literal objects created by Compiler >> #evaluate:* </span><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">are now immutable but I
think they shouldn't be. What do you think?</span><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 16px"><br>
</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"><br>
</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">Well, I think that literals producing numbers, strings, or symbols should be protected in this way. For literal arrays, I am not so sure.</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"><br>
</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">For starters, the #printString of modifiable arrays is wrong if literal arrays should be immutable:</span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"><br>
</span></div>
<div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">x := {1. 2. 3}.</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">x at: 1 put: #foo.</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">x "#(#foo 2 3) --- wrong print string!"</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">y := #(1 2 3).</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">y at: 1 put: #foo. "ModificationForbidden"</span></span></div>
</div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">Then, in the past, I have been complaining about the array cache in compiled methods:</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">someDefault</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"> ^ #(1 2 3)</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">In this case, I expected the method to always return a new array. Now, it is immutable, but that is not as expected. I think. Is it still cached?</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">***</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">In my case here, the code tries to change a LargePositiveInteger, not an array, which has always been wrong. :-) Is there a way to safely discard a LargePositiveInteger
from memory?</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">> </span></span><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">System-ul.1148 should work the issue around. Please let me know if it</span><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"> </span></div>
<span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">helped.</span>
<div><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">Not quite. I think have to manually clear the current keys in the SecurityManager first.</span></span></div>
<div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px"><br>
</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">Best,</span></span></div>
<div style=""><span style="font-family: Arial, Helvetica, sans-serif"><span style="font-size: 13px">Marcel</span></span></div>
<div class="mb_sig"></div>
</div>
<blockquote class="history_container" type="cite" style="border-left-style: solid;border-width: 1px;margin-top: 20px;margin-left: 0px;padding-left: 10px;min-width: 500px">
<p style="color: #AAAAAA; margin-top: 10px;">Am 24.03.2020 21:18:51 schrieb Levente Uzonyi <leves@caesar.elte.hu>:</p>
<div style="font-family:Arial,Helvetica,sans-serif">Hi Marcel,<br>
<br>
System-ul.1148 should work the issue around. Please let me know if it <br>
helped.<br>
The main issue is that literal objects created by Compiler >> #evaluate:* <br>
are now immutable but I think they shouldn't be. What do you think?<br>
<br>
<br>
Levente<br>
<br>
On Tue, 24 Mar 2020, Marcel Taeumel wrote:<br>
<br>
> Hi, there.<br>
> <br>
> I just wanted to save a 32-bit image (Update 19541, VM 202003021730, Windows 10) under a new filename.<br>
> <br>
> Boom! ModificationForbidden!<br>
> <br>
> Here is the interesting stack:<br>
> <br>
> Context>>modificationForbiddenFor:at:put:<br>
> LargePositiveInteger(Object)>>basicAt:put:<br>
> SecurityManager>>flushSecurityKey:<br>
> SecurityManager>>flushSecurityKeys<br>
> SecurityManager>>shutDown<br>
> SecurityManager class>>shutDown<br>
> SecurityManager class(Behavior)>>shutDown:<br>
> [] in SmalltalkImage>>send:toClassesNamedIn:with:<br>
> OrderedCollection>>do:<br>
> SmalltalkImage>>send:toClassesNamedIn:with:<br>
> SmalltalkImage>>processShutDownList:<br>
> <br>
> Well, that code tries to change a LargePositiveInteger:<br>
> <br>
> SecurityManager >> flushSecurityKey: aKey<br>
> "Flush a security key"<br>
> | n |<br>
> n := aKey first.<br>
> 1 to: n basicSize do:[:i| n basicAt: i put: 0].<br>
> n := aKey second.<br>
> 1 to: n basicSize do:[:i| n basicAt: i put: 0].<br>
> <br>
> How to fix that without breaking security measures or the underlying concept?<br>
> <br>
> Best,<br>
> Marcel<br>
> <br>
><br>
<br>
</div>
</blockquote>
</div>
</div>
</div></blockquote>
</div></body>