Summary:
This is a follow up of D52008 and should make the analyzer being able to handle perfect forwardings in real world cases where forwardings are done through multiple layers of function calls with `std::forward`.
Fixes PR38891.
Reviewers: lebedev.ri, JonasToth, george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D52120
llvm-svn: 342409
Summary:
We used to treat an `Expr` mutated whenever it's passed as non-const
reference argument to a function. This results in false positives in
cases like this:
```
int x;
std::vector<int> v;
v.emplace_back(x); // `x` is passed as non-const reference to `emplace_back`
```
In theory the false positives can be suppressed with
`v.emplace_back(std::as_const(x))` but that's considered overly verbose,
inconsistent with existing code and spammy as diags.
This diff handles such cases by following into the function definition
and see whether the argument is mutated inside.
Reviewers: lebedev.ri, JonasToth, george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D52008
llvm-svn: 342271
Summary:
This is 1/2 of moving ExprMutationAnalyzer from clangtidy to
clang/Analysis.
This diff along simply copies the ExprMutationAnalyzer over with trivial
modifications (e.g. include path, namespace)
2/2 will migrate existing usage of ExprMutationAnalyzer and remove the
original copy inside clangtidy.
Reviewers: george.karpenkov
Subscribers: mgorny, xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits, JonasToth
Differential Revision: https://reviews.llvm.org/D51948
llvm-svn: 341994
Shuai Wang