[PATCH] D44883: [Sema] Extend -Wself-assign and -Wself-assign-field to warn on overloaded self-assignment (classes)

[Nico Weber via Phabricator via cfe-commits]

thakis added a comment.

In https://reviews.llvm.org/D44883#1048751, @dblaikie wrote:

> Historically Clang's policy on warnings was, I think, much more
>  conservative than it seems to be today. There was a strong desire not to
>  implement off-by-default warnings, and to have warnings with an
>  exceptionally low false-positive rate - maybe the user-defined operator
>  detection was either assumed to, or demonstrated to, have a sufficiently
>  high false positive rate to not meet that high bar.


This is still the case. For a new warning, you should evaluate some large open-source codebase and measure true positive and false positive rate and post the numbers here.

> (as for the flag splitting - that was sometimes done if the new variant of
>  a flag had enough bug-finding power that an existing codebase using the
>  existing flag behavior would need significant cleanup - by having the new
>  functionality under another flag name, existing codebases upgrading to a
>  newer compiler wouldn't be forced to either do all that cleanup up-front or
>  disable the flag & risk regressions... )




Repository:
  rC Clang

https://reviews.llvm.org/D44883