[lldb] Fix misaligned loads violation in DataExtractor (#163880) #11653
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The implementation of the templated `Get` function contains UB. For example, the "GetDoubleUnaligned" unit test causes `Get` to perform an unaligned 8 byte read. This violates the `double` alignment requirement. Furthermore, it violates strict aliasing rules in C++. (We construct a `const double *` from a `const uint8_t *` and perform a read on the resulting double pointer). DataExtractor should be able to read unaligned data to deal with different data formats, but we need to be careful to not perform unaligned reads/writes or violate strict aliasing rules. rdar://160385383 (cherry picked from commit 40d4ea6)
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@swift-ci please test |
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The implementation of the templated
Getfunction contains UB. For example, the "GetDoubleUnaligned" unit test causesGetto perform an unaligned 8 byte read. This violates thedoublealignment requirement. Furthermore, it violates strict aliasing rules in C++. (We construct aconst double *from aconst uint8_t *and perform a read on the resulting double pointer).DataExtractor should be able to read unaligned data to deal with different data formats, but we need to be careful to not perform unaligned reads/writes or violate strict aliasing rules.
rdar://160385383
(cherry picked from commit 40d4ea6)