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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Integrated assembler allows trailing instruction prefixes"
href="https://bugs.llvm.org/show_bug.cgi?id=52405">52405</a>
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<th>Summary</th>
<td>Integrated assembler allows trailing instruction prefixes
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<th>Product</th>
<td>clang
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<th>Version</th>
<td>unspecified
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<th>Hardware</th>
<td>PC
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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
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>-New Bugs
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>me@smitop.com
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<th>CC</th>
<td>htmldeveloper@gmail.com, llvm-bugs@lists.llvm.org, neeilans@live.com, richard-llvm@metafoo.co.uk
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<pre>The LLVM integrated assembler incorrectly allows x86 instruction prefixes (like
LOCK) without an actual instruction being prefixed. This should be rejected
since LOCK isn't valid by itself: it's an instruction prefix that needs to be
followed by an actual instruction. For example:
int main() {
__asm__("lock");
}
The result is "Illegal instruction (core dumped)", since LOCK by itself isn't
an instruction. This issue also occurs with (unstable) inline assembly in Rust
(<a href="https://github.com/rust-lang/rust/issues/82314">https://github.com/rust-lang/rust/issues/82314</a>).</pre>
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