Commit Graph

3 Commits

Author SHA1 Message Date
Malcolm Parsons 87a036259b [Sema] Add warning for unused lambda captures
Summary:
Warn when a lambda explicitly captures something that is not used in its body.

The warning is part of -Wunused and can be enabled with -Wunused-lambda-capture.

Reviewers: rsmith, arphaman, jbcoe, aaron.ballman

Subscribers: Quuxplusone, arphaman, cfe-commits

Differential Revision: https://reviews.llvm.org/D28467

llvm-svn: 291905
2017-01-13 15:01:06 +00:00
Douglas Gregor 680e9e018d Improve our handling of lambda expressions that occur within default
arguments. There are two aspects to this:

  - Make sure that when marking the declarations referenced in a
  default argument, we don't try to mark local variables, both because
  it's a waste of time and because the semantics are wrong: we're not
  in a place where we could capture these variables again even if it
  did make sense.
  - When a lambda expression occurs in a default argument of a
  function template, make sure that the corresponding closure type is
  considered dependent, so that it will get properly instantiated. The
  second bit is a bit of a hack; to fix it properly, we may have to
  rearchitect our handling of default arguments, parsing them only
  after creating the function definition. However, I'd like to
  separate that work from the lambdas work.

llvm-svn: 151076
2012-02-21 19:11:17 +00:00
Douglas Gregor f0d495100c Implement C++11 [expr.lambda.prim]p13, which prohibits lambdas in
default arguments if in fact those lambdas capture any entity.

llvm-svn: 150282
2012-02-10 23:30:22 +00:00