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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/106784] New: Add __is_convertible built-in
Date: Wed, 31 Aug 2022 10:41:10 +0000
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 13.0
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X-Bugzilla-Severity: enhancement
X-Bugzilla-Who: redi at gcc dot gnu.org
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106784

            Bug ID: 106784
           Summary: Add __is_convertible built-in
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---

This is supported by Clang already, and would be very beneficial for libstd=
c++.
The std::is_convertible (and is_nothrow_convertible) type trait is used wid=
ely
in the std::lib, but is currently implemented in pure C++ as a class templa=
te.
A built-in would improve compile times.

We already have __is_constructible and __is_assignable, and the nothrow for=
ms
of those.=