Re:Towards fearless SIMD, 7 years later
by grandempire on Sunday March 30, 2025 @07:37PM
(#43528939)
That’s not true.
A conforming implementation may chose to melt your computer - and you can choose to not use that implementation. But clang and gcc will never melt your Linux.
Once again, a real life example where that is relevant is an embedded device with no memory protection. If you overwrite a buffer you can overwrite the OS code - breaking your computer and requiring you to flash the memory.
It seems there is a lot of misguided accusations going around about who misunderstands UB.
> But clang and gcc will never melt your Linux.
If you use gcc or clang to compile your kernel, they will happily melt your Linux.
Re:Towards fearless SIMD, 7 years later
by grandempire on Monday March 31, 2025 @12:38AM
(#43531112)
If you're referring to what might happen when you overwrite a buffer in privileged kernel code, yes - but that is true regardless of clang, gcc, or what the C standard says about UB.
Ok, clang will not directly melt my computer because clang just generates code, but imagine this:
if somewhere else the code access invalid pointer, clang may decide to remove this condition altogether because it thinks it must be dead code, for example. And running this code will melt the computer even though the programmer thought this wouldn't be possible.