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Posted <time class="published" datetime="2022-11-16T00:00:00-05:00">Wed 16 November 2022</time>
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<p><em>This post is part 5 of the arduino-scripting series:</em></p>
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<li >
<a href='https://dragoncoder047.github.io/blog/2022/ulisp-thoughts'>uLisp Thoughts</a>
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<a href='https://dragoncoder047.github.io/blog/2022/partcl'>ParTcl</a>
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<a href='https://dragoncoder047.github.io/blog/2022/scratching-my-head-again'>Scratching My Head Again</a>
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<a href='https://dragoncoder047.github.io/blog/2022/some-unrelated-ideas'>Some Unrelated Ideas</a>
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<a href='https://dragoncoder047.github.io/blog/2022/segfaults'>Segfaults</a>
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<a href='https://dragoncoder047.github.io/blog/2023/lilduino'>LILduino</a>
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<p>Today I did a little more work on my programming language TEHSSL. And in testing it, I discovered some anomalies.</p>
<p>The first one is that – because of a typo on my part – testing TEHSSL will occasionally segfault when it tries to print the type of the “next” object after freeing the last one – there is no “next object”, so it dereferences a null pointer and crashes. I fixed that, and it appears to work. However, it worked just fine when I pasted it into <a href="https://cpp.sh">cpp.sh</a>, and didn’t hang or anything, so I’m not sure what’s up with that.</p>
<p>Valgrind reports no memory leaks from the garpage collector after I fixed things (woohoo!), so that’s good. However, in testing those bugs, I discovered another anomaly: when the tests de-allocate and free everything at the end, it prints out how many objects it freed. This count varies based on the compiler – without me changing any code at all!!</p>
<p>When I run <code class="language-bash highlight">make test</code> (i.e. running it natively on my computer, using <code class="language-bash highlight">g++</code>), the output shows <a href="https://github.com/dragoncoder047/tehssl/blob/ea16652/test_reports/output.txt#L271">56 objects freed</a> at the end.</p>
<p>When I paste it into cpp.sh (which uses Emscripten), it says there are 51 objects freed.</p>
<p>What happened to the other 5 objects? Is it something to do with Emscripten vs <code class="language-bash highlight">g++</code>? I’m not sure. But it has no memory leaks, and that’s what I am really happy about.</p>
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<p><strong>Related Posts</strong></p>
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<li><a href="https://dragoncoder047.github.io/blog/2024/pointer-soup">Pointer Soup</a></li>
<li><a href="https://dragoncoder047.github.io/blog/2024/a-hash-mapped-mess">A Hash-Mapped Mess</a></li>
<li><a href="https://dragoncoder047.github.io/blog/2024/the-lesser-of-two-evils">The Lesser of Two Evils</a></li>
<li><a href="https://dragoncoder047.github.io/blog/2024/order-up">Order Up</a></li>
<li><a href="https://dragoncoder047.github.io/blog/2023/continuations-and-the-thunk-queue">Continuations and the thunk queue</a></li>
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