[Bug libstdc++/89477] Incorrect CTAD deduction guides for set and multiset
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89477 Mike Spertus changed: What|Removed |Added CC||mike at spertus dot com --- Comment #5 from Mike Spertus --- Since this deduction comes from the standard’s set(set, Allocator) constructor, I would say that in this case the gnu behavior is conforming and the MSVC behavior is not (not implying anything here about what the standard should say, just what it does...).
[Bug c++/79316] New: Default parameter values in explicit deduction guides do not work
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79316
Bug ID: 79316
Summary: Default parameter values in explicit deduction guides
do not work
Product: gcc
Version: 7.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: mike at spertus dot com
Target Milestone: ---
When I compile the following code with gcc-7-20170122,
template struct S { S(T t) {} };
template S(T, int = 7) -> S;
I get the following error
error: default arguments are only permitted for function parameters
[-fpermissive]
I believe that the above code should be correct as deduction-guides accept a
parameter-declaration-clause, which can have default argument values. In
addition, P0433R0 contains examples of deduction guides with default arguments
(e.g., for deque).
[Bug c++/79350] New: "explicit" deduction guides don't work
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79350
Bug ID: 79350
Summary: "explicit" deduction guides don't work
Product: gcc
Version: 7.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: mike at spertus dot com
Target Milestone: ---
When I compile the following code with gcc-7-20170122,
template struct S {};
template
explicit S(T) -> S;
I get the error
error: decl-specifier in declaration of deduction guide
explicit S(T) -> S;
^~~~
test.cpp:3:1: error: ‘explicit’ outside class declaration
This is currently a bug because the current standard draft N4618 allows an
optional "explicit" in the deduction-guide grammar production
[Bug c++/105841] [12/13 Regression] Change in behavior of CTAD for alias templates
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105841 --- Comment #8 from Mike Spertus --- Thanks, Jason! My course starts in 6 minutes, so I can't look at it now but will give you feedback by 8:30AM tomorrow. Mike On Thu, Feb 9, 2023 at 3:07 PM jason at gcc dot gnu.org < gcc-bugzi...@gcc.gnu.org> wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105841 > > --- Comment #7 from Jason Merrill --- > Created attachment 5 > --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=5&action=edit > fix > > Here's a patchset to implement the standard behavior plus the CWG2664 > clarification. Mike, does this look good to you? Any additional > testcases? > > Also pushed to refs/users/jason/heads/alias-ctad in the git repository. > ( > https://gcc.gnu.org/git/?p=gcc.git;a=shortlog;h=refs/users/jason/heads/alias-ctad > ) > > -- > You are receiving this mail because: > You are on the CC list for the bug.
[Bug c++/105841] [12/13 Regression] Change in behavior of CTAD for alias templates
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105841 --- Comment #9 from Mike Spertus --- Hi Jason, Very exciting. Some additional tests: Both versions of https://godbolt.org/z/aM93PEWcz should be included in the tests. There are two versions of the deduction guides in the godbolt. Either guide should work. (They may already work, but it remains a good test). See https://mspertus.github.io/MSVC_CTAD_1428672/ for more details. In addition, the examples at https://godbolt.org/z/PjqMa8T35 should work. Do you want versions of these that do not include standard library headers? Thanks, Mike On Thu, Feb 9, 2023 at 3:26 PM wrote: > Attachments with a MIME type of "text/html" are not allowed on this > installation. > > Michael Spertus wrote: > > Thanks, Jason! My course starts in 6 minutes, so I can't look at it now > but > > will give you feedback by 8:30AM tomorrow. > > > > Mike > > > > On Thu, Feb 9, 2023 at 3:07 PM jason at gcc dot gnu.org < > > gcc-bugzi...@gcc.gnu.org> wrote: > > > > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105841 > > > > > > --- Comment #7 from Jason Merrill --- > > > Created attachment 5 > > > --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=5&action=edit > > > fix > > > > > > Here's a patchset to implement the standard behavior plus the CWG2664 > > > clarification. Mike, does this look good to you? Any additional > > > testcases? > > > > > > Also pushed to refs/users/jason/heads/alias-ctad in the git repository. > > > ( > > > > https://gcc.gnu.org/git/?p=gcc.git;a=shortlog;h=refs/users/jason/heads/alias-ctad > > > ) > > > > > > -- > > > You are receiving this mail because: > > > You are on the CC list for the bug. >
[Bug c++/105841] [12/13 Regression] Change in behavior of CTAD for alias templates
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105841 --- Comment #3 from Mike Spertus --- Thanks for the nudge, Jason. I will shake the bit rot off the POC and try to polish it to something mergeable. OK if I ping you if I have questions?
