tree 6e9648a9a7308e1cd98560592b05783108d3af77
parent 3845da998d2fda2f86c3b923ce7613ee291643d5
author Louis Dionne <ldionne@apple.com> 1554999296 +0000
committer Louis Dionne <ldionne@apple.com> 1554999296 +0000

[libc++] Make sure we don't eagerly diagnose non-const comparators for containers of incomplete types

Summary:
In r348529, I improved the library-defined diagnostic for using containers
with a non-const comparator/hasher. However, the check is now performed
too early, which leads to the diagnostic being emitted in cases where it
shouldn't. See PR41360 for details.

This patch moves the diagnostic to the destructor of the containers, which
means that the diagnostic will only be emitted when the container is instantiated
at a point where the comparator and the key/value are required to be complete.
We still retain better diagnostics than before r348529, because the diagnostics
are performed in the containers themselves instead of __tree and __hash_table.

As a drive-by fix, I improved the diagnostic to mention that we can't find
a _viable_ const call operator, as suggested by EricWF in PR41360.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits, zoecarver

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60540

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@358189 91177308-0d34-0410-b5e6-96231b3b80d8