[PaulDavisThe1st]

> Languages like Rust include these settings in symbol names as a hash to prevent these kinds of issues by design.

Historically, C++ compilers' name mangling scheme for symbols did precisely the same thing. The 2000-2008 period for gcc was particularly painful since the compiler developers really used it very frequently, to "prevent these kinds of issues by design". The only reason most C++ developers don't think about this much any more is that most C++ compilers haven't needed to change their demangling algorithm for a decade or more.

[MontagFTB]

C++’s name mangling scheme handles some things like namespaces and overloading, but it does not account for other settings that can affect the ABI layer of the routine, like compile time switches or optimization level.

[PaulDavisThe1st]

The name mangling scheme was changed to reflect things other than namespaces and overloading, it was modified to reflect fundamental compiler version incompatibilities (i.e. the ABI)

Optimization level should never cause link time or run time issues; if it does I'd consider that a compiler/linker bug, not an issue with the language.