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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - clang constant-folds away runtime test of stack alignment"
href="https://bugs.llvm.org/show_bug.cgi?id=45479">45479</a>
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<th>Summary</th>
<td>clang constant-folds away runtime test of stack alignment
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<th>Product</th>
<td>libraries
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<th>Version</th>
<td>trunk
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<th>Hardware</th>
<td>All
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>normal
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>Backend: AArch64
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>roland@hack.frob.com
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<th>CC</th>
<td>arnaud.degrandmaison@arm.com, llvm-bugs@lists.llvm.org, smithp352@googlemail.com, Ties.Stuij@arm.com
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<pre>Created <span class=""><a href="attachment.cgi?id=23333" name="attach_23333" title="reproducer (preprocessed C++)">attachment 23333</a> <a href="attachment.cgi?id=23333&action=edit" title="reproducer (preprocessed C++)">[details]</a></span>
reproducer (preprocessed C++)
With attached reproducer, clang generates code that takes the __zx_panic path
unconditionally. The asm should force it to produce a runtime test. If that
weren't there, it would be kosher to fold away the test--but it should succeed
rather than fail. The actual address computed is correct and at runtime in the
debugger it can be seen to be 0 mod 16, so if the code checked that as it
should the test would pass.</pre>
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