https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65869
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://gcc.gnu.org/bugzill
| |a/show_bug.cgi?id=80452,
| |https://gcc.gnu.org/bugzill
| |a/show_bug.cgi?id=91427
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Some interesting history here:
GCC7.5.0 and before accepted the code in C++11, C++14 and C++17 modes
GCC8+ reject the code in C++11, C++14, and C++17 modes with the following error
message:
<source>: In function 'Derived foo()':
<source>:14:10: error: cannot bind rvalue reference of type 'Base&&' to lvalue
of type 'Base'
return result;
^~~~~~
<source>:9:5: note: initializing argument 1 of 'Derived::Derived(Base&&)'
Derived(Base&&);
^~~~~~~
GCC11+ started to accept the code in C++20 mode.
GCC8 change was due to PR 80452.
GCC11 in C++20 mode seems most likely due to PR 91427. The patch for PR 91427,
made it sound like it was defect report for earlier versions of the C++
standards too:
For the time being I'm limiting the new semantics to C++20 mode; since it
was moved as a DR, we will probably want to apply the change to other
standard modes as well once we have a better sense of the impact on
existing
code, probably in GCC 12.
