To keep ubsan happy, Use offsetof() rather than legacy equivalent #73657
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ghost
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jkotas
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Aug 9, 2022
src/coreclr/pal/inc/rt/palrt.h
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| // support for offsetof() on anything other than a standard-layout class | ||
| // is conditionally supported. | ||
| // This is more generous than the C++ standards when this code was originally written | ||
| // | ||
| // PAL_safe_offsetof is a version of offsetof that protects against an |
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You can delete this comment and PAL_safe_offsetof and replace all its occurences with just offsetof.
jkotas
reviewed
Aug 9, 2022
src/coreclr/pal/inc/rt/palrt.h
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| // overridden operator& | ||
| // overridden operator&. Note, however, C++-98 and newer | ||
| // requires offsetof to work correctly even if operator& is overloaded. | ||
| // | ||
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| #define FIELD_OFFSET(type, field) __builtin_offsetof(type, field) |
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Same for FIELD_OFFSET. You can delete the definition and replace the few uses with offsetof.
Using offsetof() will prevent various static analyzers and dynamic ubsan from complaining about indirecting through NULL.
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The test failure is #73299 |
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The existing code causes ubsan to generate a runtime error when using the &((Type *)0->field idiom.