Exposed by a related bug about visibility of default arguments of nested
templates - without the correct decl context, default template
parameters of variable templates nested in classes would have incorrect
visibility computed.
llvm-svn: 358796
The code is/was already correct for the case where a parameter is a
parameter of its enclosing lexical DeclContext (functions and classes).
But for other templates (alias and variable templates) they don't create
their own scope to be members of - in those cases, they parameter should
be considered visible if any definition of the lexical decl context is
visible.
[this should cleanup the failure on the libstdc++ modules buildbot]
[this doesn't actually fix the variable template case for a
secondary/compounding reason (its lexical decl context is incorrectly
considered to be the translation unit)]
Test covers all 4 kinds of templates with default args, including a
regression test for the still broken variable template case.
Reviewers: rsmith
Differential Revision: https://reviews.llvm.org/D60892
llvm-svn: 358795