fixed #14261/#14902 - Regex: added std::regex implementation

[firewave]

No description provided.

[firewave]

Might make sense to be able to specify the type via a rule file as well. That would also allow to mix and match the engines depending on required performance/features. Or maybe even only allow it via a file so to not add another CLI option and not having to deal with the left-to-right issues.

[firewave]

This will only add the additional engine. I will also do some performance tests.

The follow-up steps are:

• implement PCRE2 as an additional engine and make it optional via a new build flag
• make std::regex the default and deprecate HAVE_RULES and PCRE1 so the feature works without any build dependencies
• remove HAVE_RULES and PCRE1 shortly after (most distros have already dropped the dependency since the library has long been EOL)

[danmar]

thanks for working on this. 👍

[firewave]

Might make sense to be able to specify the type via a rule file as well. That would also allow to mix and match the engines depending on required performance/features. Or maybe even only allow it via a file so to not add another CLI option and not having to deal with the left-to-right issues.

@danmar any comment on this?

[firewave]

No comment so I will go with the way to specify the engine via XML only and not providing a CLI option for it.

[firewave]

The follow-up steps are:

I filed some tickets for those:
https://trac.cppcheck.net/ticket/14262
https://trac.cppcheck.net/ticket/14263

[firewave]

The documentation on how to use rules is unfortunately some PDFs hosted at Sourceforge so there is nowhere to add the new field. I filed https://trac.cppcheck.net/ticket/14264 about migrating the documentation.

[firewave]

Great - std::regex appears to behave differently in Visual Studio:

D:\a\cppcheck\cppcheck\test\testregex.cpp:181(TestRegExStd::exactmatch): Assertion failed. 
Expected: 
0

Actual: 
2

Why am I not surprised?!

And on macos testrunner is not showing the failed test:

TestVarID::structuredBindings


Testing Complete
Number of tests: 5164
Number of todos: 371
make: *** [test] Error 1
Error: Process completed with exit code 2.

[firewave]

Great - std::regex appears to behave differently in Visual Studio:

Apparently std::regex is partially broken in the current Visual Studio version (not sure if it is what affects the test): https://developercommunity.visualstudio.com/t/std::regex-gives-a-different-result-in-m/10417784

So that partially derails the plan going forward and makes things more awkward. And I have not even profiled it yet...

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[firewave]

Coincidentally Visual Studio 2026 was released just a few hours ago and I can confirm that the test passes in it.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[danmar]

Thanks for working on this. Sorry I didnt reply to your question. An option in the XML sounds fine.

My goal is to eventually drop the pcre dependency completely. In gentle manner.. deprecate pcre and tell users to try to migrate to std::regex and say that unless they complain we remove support for pcre in some version 2.x..

[firewave]

My goal is to eventually drop the pcre dependency completely. In gentle manner.. deprecate pcre and tell users to try to migrate to std::regex and say that unless they complain we remove support for pcre in some version 2.x..

This is already part of this and the PCRE2 work.