https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83445
Alexander Karzhenkov <karzh at mail dot ru> changed:
What |Removed |Added
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CC| |karzh at mail dot ru
--- Comment #1 from Alexander Karzhenkov <karzh at mail dot ru> ---
Candidate functions considered by overload resolution are
Target::Target(Source const&);
constexpr Target::Target(Target const&);
constexpr Target::Target(Target&&);
The first one doesn't require any user-defined conversion and therefore should
win.
The bug appears to be fixed in gcc 8, but it occurs again in gcc 9 and later
versions.