diff options
author | Noel Grandin <noel.grandin@collabora.co.uk> | 2020-02-21 12:24:15 +0200 |
---|---|---|
committer | Noel Grandin <noel.grandin@collabora.co.uk> | 2020-02-21 14:48:10 +0100 |
commit | 3aca35f1505fa552eaa316a2d47a60ef52646525 (patch) | |
tree | 9ce22f25a49f77418d98a926f0616630cd1fdd2a | |
parent | b7922b56e2dcf1dc1abbf5574bcb672068fa8dbd (diff) |
loplugin:sequenceloop improve rvalue detection
to avoid false positives
Change-Id: Id20eb0837fa6764139af3fc4481c768700ec2dad
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/89184
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
-rw-r--r-- | compilerplugins/clang/sequenceloop.cxx | 6 | ||||
-rw-r--r-- | compilerplugins/clang/test/sequenceloop.cxx | 9 |
2 files changed, 15 insertions, 0 deletions
diff --git a/compilerplugins/clang/sequenceloop.cxx b/compilerplugins/clang/sequenceloop.cxx index 7f14d6c4d951..9a620f26be52 100644 --- a/compilerplugins/clang/sequenceloop.cxx +++ b/compilerplugins/clang/sequenceloop.cxx @@ -63,6 +63,12 @@ bool SequenceLoop::VisitCXXForRangeStmt(CXXForRangeStmt const* forStmt) if (!tc2.LvalueReference().Const()) return true; + // bit awkward, but the only way to sniff out if we're being passed a value or a reference + auto rangeDeclStmt = dyn_cast<DeclStmt>(forStmt->getRangeStmt()); + auto rangeVarDecl = dyn_cast<VarDecl>(rangeDeclStmt->getSingleDecl()); + if (rangeVarDecl->getType()->isRValueReferenceType()) + return true; + report(DiagnosticsEngine::Warning, ("use std::as_const, or otherwise make the for-range-initializer expression const, to" " avoid creating a copy of the Sequence"), diff --git a/compilerplugins/clang/test/sequenceloop.cxx b/compilerplugins/clang/test/sequenceloop.cxx index e124fda27093..41cb32f0495a 100644 --- a/compilerplugins/clang/test/sequenceloop.cxx +++ b/compilerplugins/clang/test/sequenceloop.cxx @@ -30,6 +30,15 @@ void foo2(const css::uno::Sequence<css::uno::Reference<css::uno::XInterface>>& a for (const auto& x : aSeq) x.get(); } + +css::uno::Sequence<css::uno::Reference<css::uno::XInterface>> getSequenceByValue(); + +// no warning expected +void foo3() +{ + for (const auto& x : getSequenceByValue()) + x.get(); +} }; /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */ |