Commit Graph

7 Commits

Author SHA1 Message Date
Richard Smith 9975dc38bf Defer checking for mismatches between the deletedness of and overriding
function and an overridden function until we know whether the overriding
function is deleted.

We previously did these checks when we first built the declaration,
which was too soon in some cases. We now defer all these checks to the
end of the class.

Also add missing check that a consteval function cannot override a
non-consteval function and vice versa.
2020-03-12 13:07:22 -07:00
Richard Smith 9b2c5e7c44 [cxx2a] P0641R2: (Some) type mismatches on defaulted functions only
render the function deleted instead of rendering the program ill-formed.

This change also adds an enabled-by-default warning for the case where
an explicitly-defaulted special member function of a non-template class
is implicitly deleted by the type checking rules. (This fires either due
to this language change or due to pre-C++20 reasons for the member being
implicitly deleted). I've tested this on a large codebase and found only
bugs (where the program means something that's clearly different from
what the programmer intended), so this is enabled by default, but we
should revisit this if there are problems with this being enabled by
default.

llvm-svn: 343285
2018-09-28 01:16:43 +00:00
Richard Smith 1338122b25 Add context note to diagnostics that occur while declaring an implicit special member function.
llvm-svn: 296020
2017-02-23 21:43:43 +00:00
Richard Smith f3cec65d01 When diagnosing that a defaulted function is ill-formed because it would be
implicitly deleted and overrides a non-deleted function, explain why the
function is deleted. For PR30844.

llvm-svn: 285610
2016-10-31 18:18:29 +00:00
Richard Smith 8b86f2d401 Implement final resolution of DR1402: implicitly-declared move operators that
would be deleted are still declared, but are ignored by overload resolution.

Also, don't delete such members if a subobject has no corresponding move
operation and a non-trivial copy. This causes us to implicitly declare move
operations in more cases, but risks move-assigning virtual bases multiple
times in some circumstances (a warning for that is to follow).

llvm-svn: 193969
2013-11-04 01:48:18 +00:00
Richard Smith b4d2a15d17 If a defaulted special member is implicitly deleted, check whether it's
overriding a non-deleted virtual function. The existing check for this doesn't
catch this case, because it fires before we mark the method as deleted.

llvm-svn: 178563
2013-04-02 19:38:47 +00:00
David Blaikie 7e414261f6 Implement C++ 10.3p16 - overrides involving deleted functions must match.
Only deleted functions may override deleted functions and non-deleted functions
may only override non-deleted functions.

llvm-svn: 166082
2012-10-17 00:47:58 +00:00