Fix regex tokenizing bug #131
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We skip a non-match character in `regex_iterator::operator++` after a zero-length match to avoid repeat matches, resulting in incorrect behavior when tokenizing with a regex to match the delimiters between tokens. Fixes [DevCom#733051](https://developercommunity.visualstudio.com/content/problem/733051/splitting-a-string-with-a-regex-returns-seemingly.html).
| @@ -26,9 +26,6 @@ _STL_DISABLE_CLANG_WARNINGS | |||
| #pragma push_macro("new") | |||
| #undef new | |||
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| // TRANSITION, Several names herein are declared as _Xxx_xxx2; in all such cases the corresponding | |||
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For folks reading, these comments were transformed into tests that aren't yet present here in GitHub (I'm working on it right now, sorry!).
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For the folks wondering why it matters: ABI.
When we change the relationship between an internal function _Fn and public function fn, we have to change the name of _Fn to avoid "old" fn in already-compiled code "in the wild" linking to freshly-compiled code and consequently calling the "new" _Fn with catastrophic results. Ditto "new" fn must not call "old" _Fn. When the change touches the function parameters, generally the mangled name of _Fn is different. If the change doesn't alter the function parameters, we'll change the name of _Fn directly, say by adding a 2.
When the name is changed directly the old name _Fn becomes available. We could then inadvertently reuse it for something else, with potentially the same catastrophic results. Rather than simply keeping a list of names to avoid - which people would have to check when writing new code - we have a test that crashes if such a name is reused.
Description
We skip a non-match character in
regex_iterator::operator++after a zero-length match to avoid repeat matches, resulting in incorrect behavior when tokenizing with a regex to match the delimiters between tokens.Fixes DevCom#733051.
[This is a replay of internal PR 203601].
Checklist:
Working Draft. (N/A)
(The version is important because clang-format's behavior sometimes changes.)
_Uglyas perhttps://eel.is/c++draft/lex.name#3.1 .
_Ugly.what happens to compile.
by an STL maintainer before CI is online, leave this unchecked for initial
submission).
members, adding virtual functions, changing whether a type is an aggregate or
trivially copyable, etc.). If unsure, leave this box unchecked and ask a
maintainer for help.