[Bug libstdc++/106248] operator>>std::basic_istream at boundary condition behave differently in different opt levels

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106248

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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           Keywords|                            |wrong-code

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This is interesting because I get the same behavior in clang with LLVM's
libc++.

Also with -std=c++20 I get the value 0 for all optimization levels.

Maybe there is undefined code here ...