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<base href="https://llvm.org/bugs/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW " title="NEW --- - [Windows] Clang doesn't support std::atomic<function pointer> with Microsoft's STL" href="https://urldefense.proofpoint.com/v2/url?u=https-3A__llvm.org_bugs_show-5Fbug.cgi-3Fid-3D23733&d=AwMBaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=pF93YEPyB-J_PERP4DUZOJDzFVX5ZQ57vQk33wu0vio&m=h0rfdaBAL2HOnbVfA3v_9LK3C4z8Z5WxgPp54bi-6uA&s=7MmCsJ5CgmQtrUMCA-sdwC78cwcAGN0RhYEWelf4I2E&e=">23733</a>
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<th>Summary</th>
<td>[Windows] Clang doesn't support std::atomic<function pointer> with Microsoft's STL
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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
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<th>OS</th>
<td>Windows NT
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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>C++
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>sebastian.redl@getdesigned.at
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<th>CC</th>
<td>dgregor@apple.com, llvmbugs@cs.uiuc.edu
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<th>Classification</th>
<td>Unclassified
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<p>
<div>
<pre>This code doesn't work with clang-cl for Visual Studio 2013:
void test() {
std::atomic<void (*)()> fptr(nullptr);
fptr.load();
}
The problem is that in atomic's implementation, all pointer atomics (which
includes pointer-to-function atomics) store a void* internally, and load()
static_casts the void* to the actual pointer type. Apparently, Microsoft's
compiler accepts a static_cast<void (*)()>((void*)0). clang-cl does not.</pre>
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