Fully initialize ev.data. #325
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On Linux systems, ev.data is an 8-byte field, but this code currently initializes only 4 bytes of the field, leaving the trailing 4 bytes unininitialized. This causes memory safety tools like Valgrind to complain. This patch no longer explicitly initializes .data, ensuring that C structure initialization will force the .data field to be zero initialized. Manual checks of the compiled binary show that the compiler correctly initializes the 4 bytes for u32 only once, so this change incurs minimal overhead.
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@swift-ci please test |
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@swift-ci please test |
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@MadCoder Sorry, I completely missed your feedback until just now! Would you prefer that I update the dispatch codebase to use |
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no that's fine, the patch you did is fine too |
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what is happening to the bots now... @swift-ci please test |
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@swift-ci please test |
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@swift-ci test |
ktopley-apple
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Dec 6, 2018
Fully initialize ev.data. Signed-off-by: Daniel A. Steffen <[email protected]>
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On Linux systems, ev.data is an 8-byte field, but this code currently initializes only 4 bytes of the field, leaving the trailing 4 bytes unininitialized. This causes memory safety tools like Valgrind to complain, as noted in #321.
This patch no longer explicitly initializes
.data, ensuring that C structure initialization will force the.datafield to be zero-initialized. Manual checks of the compiled binary show that the compiler correctly initializes the 4 bytes for.u32only once, so this change incurs minimal overhead (specifically, setting the next 4 bytes to 0).