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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Clang should never emit zero-length functions if they may be address-taken"
href="https://bugs.llvm.org/show_bug.cgi?id=33033">33033</a>
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<th>Summary</th>
<td>Clang should never emit zero-length functions if they may be address-taken
</td>
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>unspecified
</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>
</tr>
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<th>Severity</th>
<td>enhancement
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>LLVM Codegen
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
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<th>Reporter</th>
<td>peter@pcc.me.uk
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
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<p>
<div>
<pre>If the linker places a zero-length function at the same address as another
function, function pointer equality may be broken.
$ cat addr-taken.c
#include <stdio.h>
void f1() { __builtin_unreachable(); }
void f2() { __builtin_unreachable(); }
int main() {
printf("%p %p\n", &f1, &f2);
}
$ clang -Os addr-taken.c
$ ./a.out
0x400510 0x400510</pre>
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