<regex>: Fix integer overflow in _Buf and implement geometric buffer expansion - #5175

<regex>: Fix integer overflow in _Buf and implement geometric buffer expansion#5175

Stephan T. Lavavej (StephanTLavavej) merged 6 commits into

microsoft:mainmicrosoft/STL:mainfrom

muellerj2:regex-fix-integer-overflowmuellerj2/STL:regex-fix-integer-overflowCopy head branch name to clipboard