valueflow.cpp: avoid some copies related to ErrorPath#4160
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firewave
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Jun 1, 2022
| ErrorPath er = v.errorPath; | ||
| const Variable *var = getLifetimeVariable(tok2, er); | ||
| // TODO: the inserted data is never used | ||
| er.insert(er.end(), errorPath.begin(), errorPath.end()); |
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@pfultz2
Please take a look. Seems like this is inserted the wrong way.
Would be great if we could detect this but I guess it's a variant of https://trac.cppcheck.net/ticket/4593.
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@pfultz2 Please take a look.
Feel free to merge as well.
firewave
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Jun 1, 2022
| value.lifetimeScope = ValueFlow::Value::LifetimeScope::ThisValue; | ||
| value.tokvalue = tok2; | ||
| value.errorPath.push_back({tok2, "Lambda captures the 'this' variable here."}); | ||
| value.errorPath.emplace_back(tok2, "Lambda captures the 'this' variable here."); |
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I would have expected for clang-tidy to detect this but maybe that check is still in review.
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Turns out we have modernize-use-emplace disabled in our .clang-tidy config.
The detection of unnecessary temporary object was to clang-tidy just today: llvm/llvm-project@987f9cb
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Testing an
-O2build with--enable=all --inconclusiveonmame_regtestcode (with some additional local speed hacks and BoostSmallVectorapplied):Clang 13
18,349,224,671->18,347,635,685We might also be able to use
std::move()inaddErrorPath()andreanalyze().