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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - False negatives for -Wconstant-conversion in enums"
href="https://bugs.llvm.org/show_bug.cgi?id=36186">36186</a>
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<th>Summary</th>
<td>False negatives for -Wconstant-conversion in enums
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<th>Product</th>
<td>clang
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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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>enhancement
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>C++
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>smeenai@fb.com
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<th>CC</th>
<td>compnerd@compnerd.org, dgregor@apple.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<pre>% cat enum.cpp
enum { A = 128 };
void f(signed char);
void g() { f(A); }
% clang -target x86_64-linux -fsyntax-only -Wconstant-conversion enum.cpp
The implicit conversion from the enumeration type (which should be an unsigned
8 bit type) to the function parameter (a signed 8 bit type) causes a value
change from 128 to -128, but -Wconstant-conversion doesn't catch that. Upping
the enumeration value to anything above 255 shows the expected diagnostic.</pre>
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