The standard says:
The optional requires-clause ([temp.pre]) in an init-declarator or
member-declarator shall be present only if the declarator declares a
templated function ([dcl.fct]).
This implements that limitation, and updates the tests to the best of my
ability to capture the intent of the original checks.
Differential Revision: https://reviews.llvm.org/D125711
Based on post-commit review discussion on
2bd8493847 with Richard Smith.
Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).
This was originally committed in 277623f4d5
Reverted in f9ad1d1c77 due to breakages
outside of clang - lldb seems to have some strange/strong dependence on
"char [N]" versus "char[N]" when printing strings (not due to that name
appearing in DWARF, but probably due to using clang to stringify type
names) that'll need to be addressed, plus a few other odds and ends in
other subprojects (clang-tools-extra, compiler-rt, etc).
Looks like lldb has some issues with this - somehow it causes lldb to
treat a "char[N]" type as an array of chars (prints them out
individually) but a "char [N]" is printed as a string. (even though the
DWARF doesn't have this string in it - it's something to do with the
string lldb generates for itself using clang)
This reverts commit 277623f4d5.
Based on post-commit review discussion on
2bd8493847 with Richard Smith.
Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).
A constrained function with an auto return type would have it's definition
instantiated in order to deduce the auto return type before the constraints
are checked.
Move the constraints check after the return type deduction.
Now with concepts support merged and mostly complete, we do not need -fconcepts-ts
(which was also misleading as we were not implementing the TS) and can enable
concepts features under C++2a. A warning will be generated if users still attempt
to use -fconcepts-ts.
Function trailing requires clauses now parsed, supported in overload resolution and when calling, referencing and taking the address of functions or function templates.
Differential Revision: https://reviews.llvm.org/D43357
Erich Keane