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<p>Hi all! :-)</p>
<p><b><br>
</b></p>
<p><b>Steps to reproduce:</b></p>
<p>Do it:</p>
<p></p>
<blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;">
<div>[true]</div>
<div><span style="white-space:pre"></span>whileTrue;</div>
<div><span style="white-space:pre"></span>whileFalse</div>
</blockquote>
<div></div>
<div><br>
</div>
<div><b>Expected behavior:</b></div>
<div>The script is compiled and executed (and an infinite loop occurs).</div>
<div><br>
</div>
<div><b>Actual behavior:</b></div>
<div><img size="43032" contenttype="image/png" id="img437184" style="max-width: 99.9%; user-select: none;" contextid="img325" tabindex="0" src="cid:60074202-9794-48ae-a5fd-57507c88211b"><br>
</div>
<div><br>
</div>
<div><b>Further investigations:</b></div>
<div>In #<span>analyseTempsWithin:rootNode:assignmentPools:, the inner BlockNode [true] is not computed a blockExtent, because it is optimized.</span></div>
<div><span>This leads to a nil key in the ByteCodeEncoder's blockExtentsToLocals.</span></div>
<div><span>A fast solution would be to skip nil blockExtents in #<span>noteBlockExtent:hasLocals:, but that's a dirty workaround.</span></span></div>
<div><span><span><br>
</span></span></div>
<div><span><span><b>Similar bug:</b></span></span></div>
<div><span><span>Try to do:</span></span></div>
<blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;">
<div><span><span>
<div>Object newSubclass compile: 'iWontCompile: foo</div>
</span></span></div>
<div><span><span>
<div><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; white-space: pre;"></span>foo.</div>
</span></span></div>
<div><span><span>
<div><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; white-space: pre;"></span>[true]</div>
</span></span></div>
<div><span><span>
<div><span style="white-space:pre"><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; white-space: pre;"></span></span>whileTrue;</div>
</span></span></div>
<div><span><span>
<div><span style="white-space:pre"><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; white-space: pre;"></span></span>whileFalse'</div>
</span></span></div>
</blockquote>
<div><span><span>
<div></div>
<div></div>
<div></div>
</span></span></div>
<div>Fails with:</div>
<div><img size="38107" contenttype="image/png" id="img760294" style="max-width: 99.9%; user-select: none;" contextid="img995373" tabindex="0" src="cid:8ddf552d-c1a1-4498-9284-472389ef8208"><br>
</div>
<div>Again, the problem is that blockExtent isNil.</div>
<div><br>
</div>
<div><b>Workaround:</b></div>
<div>Send #yourself to the block before sending the cascade. This prevents the receiver from being optimized.</div>
<div><br>
</div>
<div>Please note that this problem does not only occur in case of special blocks. For example, <span style="font-size: 12pt;">[Sensor anyButtonPressed] </span><span style="font-size: 12pt;">whileTrue; </span><span style="font-size: 12pt;">whileFalse fails as
well.</span></div>
<div><br>
</div>
<div><br>
</div>
<div>How to fix this appropriately? I'm not sure whether I understand the whole idea of blockExtent so far. According to the documentation comment, it should be okay to be nil; however, the #blockExtent comment does not mention this fact.</div>
<div>Please see the attached changeset for an approach to fix the issue. All tests from KernelTests-Methods and most tests from Test-Compiler pass it, except of the testAllNodePCs* which time out in my fresh image. It would be great to hear if this is the right
way to solve the bug, or just extending a workaround :-)</div>
<div><br>
</div>
<div>Best,</div>
<div>Christoph</div>
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