https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109203
Jiang An <de34 at live dot cn> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |de34 at live dot cn --- Comment #6 from Jiang An <de34 at live dot cn> --- libstdc++ has (unfortunately?) implemented the tuple-or-pair strategy in P2321. The strategy is dropped by P2165. It seems that if std::tuple is unconditionally used, this issue will be resolved. This issue will also be resolved once LWG3865 gets implemented.