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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Remove -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang"
href="https://bugs.llvm.org/show_bug.cgi?id=45497">45497</a>
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<th>Summary</th>
<td>Remove -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
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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>PC
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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>enhancement
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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>keescook@chromium.org
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<th>CC</th>
<td>blitzrakete@gmail.com, dgregor@apple.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<pre>Using -ftrivial-auto-var-init=zero is preferred by the Linux kernel for both
semantics and performance.
It's worth noting that Linus Torvalds would very much like to see zero-init be
a by-default change to how the Linux kernel's C "dialect" behaves:
<a href="https://lore.kernel.org/lkml/CAHk-=wgTM+cN7zyUZacGQDv3DuuoA4LORNPWgb1Y_Z1p4iedNQ@mail.gmail.com/">https://lore.kernel.org/lkml/CAHk-=wgTM+cN7zyUZacGQDv3DuuoA4LORNPWgb1Y_Z1p4iedNQ@mail.gmail.com/</a>
"So I'd like the zeroing of local variables to be a native compiler option..."
"This, btw, is why I also think that the "initialize with poison" is
pointless and wrong."
The performance issue is also very real (as noted in the thread above too).
Zero init is faster, and for making such a large change to the kernel, we want
to more efficient option. Can we please remove
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang ?</pre>
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