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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Miscompilation when using -g, -fmodules and non-module headers"
href="https://bugs.llvm.org/show_bug.cgi?id=42955">42955</a>
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<th>Summary</th>
<td>Miscompilation when using -g, -fmodules and non-module headers
</td>
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>9.0
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>Modules
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
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<th>Reporter</th>
<td>yshuiv7@gmail.com
</td>
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<th>CC</th>
<td>dgregor@apple.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<pre>I have not idea what is causing this, but here is the code that triggers the
bug:
<a href="https://github.com/yshui/bugs/tree/clang-8.0.1-2019-08-19">https://github.com/yshui/bugs/tree/clang-8.0.1-2019-08-19</a>
The clang command is in test.sh.
The miscompiled function is __list_insert_between,
new_->prev = prev;
is somehow compiled as
new_->next = prev;
Doing either of these fixes the problem:
* Remove -g from clang command line
* Include "list.h" directly in x.c
* Remove the "triggers_the_bug" function
Tested on 8.0.1 and 9.0.0 r366556 (or git commit
1931d3cb20a00da732c5210b123656632982fde0)</pre>
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