* [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class
[not found] <bug-93807-4@http.gcc.gnu.org/bugzilla/>
@ 2020-04-21 22:05 ` mpolacek at gcc dot gnu.org
2020-04-21 22:18 ` mpolacek at gcc dot gnu.org
` (2 subsequent siblings)
3 siblings, 0 replies; 4+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2020-04-21 22:05 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93807
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Status|UNCONFIRMED |ASSIGNED
Keywords|accepts-invalid |
CC| |mpolacek at gcc dot gnu.org
Last reconfirmed| |2020-04-21
Assignee|unassigned at gcc dot gnu.org |mpolacek at gcc dot gnu.org
--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I think this is valid code: C++20 [temp.names]/2 says "A name is also
considered to refer to a template if it is an unqualified-id followed by a <
and name lookup either finds one or more functions or finds nothing." so when
we're parsing
constexpr friend bool operator==<T>(T lhs, const Foo& rhs);
we treat "operator==" as a template name, because name lookup of "operator=="
found nothing and we have an operator-function-id, which is an unqualified-id.
So the declaration isn't needed to treat "operator==<T>" as a template-id.
I'll add the test.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class
[not found] <bug-93807-4@http.gcc.gnu.org/bugzilla/>
2020-04-21 22:05 ` [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class mpolacek at gcc dot gnu.org
@ 2020-04-21 22:18 ` mpolacek at gcc dot gnu.org
2020-04-22 19:54 ` cvs-commit at gcc dot gnu.org
2020-04-22 19:55 ` mpolacek at gcc dot gnu.org
3 siblings, 0 replies; 4+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2020-04-21 22:18 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93807
--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
(Clang doesn't accept this code because it doesn't implement P0846R0 yet.)
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class
[not found] <bug-93807-4@http.gcc.gnu.org/bugzilla/>
2020-04-21 22:05 ` [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class mpolacek at gcc dot gnu.org
2020-04-21 22:18 ` mpolacek at gcc dot gnu.org
@ 2020-04-22 19:54 ` cvs-commit at gcc dot gnu.org
2020-04-22 19:55 ` mpolacek at gcc dot gnu.org
3 siblings, 0 replies; 4+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2020-04-22 19:54 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93807
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Marek Polacek <mpolacek@gcc.gnu.org>:
https://gcc.gnu.org/g:edfa7c684d329708dcee733fcb552bed9d931621
commit r10-7894-gedfa7c684d329708dcee733fcb552bed9d931621
Author: Marek Polacek <polacek@redhat.com>
Date: Tue Apr 21 18:11:33 2020 -0400
c++: Add test for c++/93807
This PR was initially accepts-invalid, but I think it's actually valid
C++20 code. My reasoning is that in C++20 we no longer require the
declaration of operator== (#if-defed in the test), because C++20's
[temp.names]/2 says "A name is also considered to refer to a template
if it is an unqualified-id followed by a < and name lookup either finds
one or more functions or finds nothing." so when we're parsing
constexpr friend bool operator==<T>(T lhs, const Foo& rhs);
we treat "operator==" as a template name, because name lookup of
"operator==" found nothing and we have an operator-function-id, which is
an unqualified-id, and it's followed by a <. So the declaration isn't
needed to treat "operator==<T>" as a template-id.
PR c++/93807
* g++.dg/cpp2a/fn-template20.C: New test.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/93807] -std=c++2a allows to omit out-of-class declaration in template class
[not found] <bug-93807-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2020-04-22 19:54 ` cvs-commit at gcc dot gnu.org
@ 2020-04-22 19:55 ` mpolacek at gcc dot gnu.org
3 siblings, 0 replies; 4+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2020-04-22 19:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93807
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution|--- |FIXED
--- Comment #5 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Test added.
^ permalink raw reply [flat|nested] 4+ messages in thread