Remove padding bytes risk in dbghelp with MaybeUninit #737
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As reported in rust-lang#720, there is a risk that the current code, by using &mut to a struct with padding fields, interacts in ways that cause padding bytes to be written to bytes that Rust originally thought were real and initialized. If this assumption persists forward in time far enough, this could possibly cause an issue due to compiler optimizations. This seems unlikely, but we can fix this by using MaybeUninit and then addressing the data using raw pointers only. That way, we do not have to depend on all the data being in initialized states even after calling SymFromAddrW. Except for the specific fields we read, of course.
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ChrisDenton
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As reported in #720, there is a risk that the current code, by using &mut to a struct with padding fields, interacts in ways that cause padding bytes to be written to bytes that Rust originally thought were real and initialized. If this assumption persists forward in time far enough, this could possibly cause an issue due to compiler optimizations.
This seems unlikely, but we can fix this by using MaybeUninit and then addressing the data using raw pointers only. That way, we do not have to depend on all the data being in initialized states even after calling SymFromAddrW. Except for the specific fields we read, of course.
Fixes #720