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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Clang generates incorrect code when compiling chromium's sql_transaction.cc"
href="https://bugs.llvm.org/show_bug.cgi?id=39574">39574</a>
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<th>Summary</th>
<td>Clang generates incorrect code when compiling chromium's sql_transaction.cc
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<th>Product</th>
<td>clang
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<th>Version</th>
<td>trunk
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<th>Hardware</th>
<td>Other
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<th>OS</th>
<td>Linux
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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>ptworek@vewd.com
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<th>CC</th>
<td>dgregor@apple.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<pre>I've recently run into strange crashes in a chromium based product compiled
with the recent HEAD versions of clang. After some investigation I've
discovered that blink::SQLTransaction::StateFunctionFor seems to return bad
pointers. This is rather strange since the function itself is pretty trivial
<a href="https://cs.chromium.org/chromium/src/third_party/blink/renderer/modules/webdatabase/sql_transaction.cc?q=sql_transaction.cc&sq=package:chromium&dr&l=136">https://cs.chromium.org/chromium/src/third_party/blink/renderer/modules/webdatabase/sql_transaction.cc?q=sql_transaction.cc&sq=package:chromium&dr&l=136</a>.
What is even more interesting, the problem occurs only if this one specific
function is compiled with optimizations enabled. Adding "pragma clang optimize
on/off" around the function fixes the problem. Another way to solve it is to
simply comment out the second DCHECK in this function. The DCHECK failure is
not a problem however, only its presence affects the generated code somehow.
The issue happens only on armv7, I cannot reproduce it on x86_64.
So far I've been unable to prepare a minimized TC that reproduces this problem
outside of chromium codebase.</pre>
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