libstdc++-9-dev 9.2.1-19ubuntu1 (amd64 binary) in ubuntu focal

 This package contains the headers and static library files necessary for
 building C++ programs which use libstdc++.
 .
 libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which
 was included up to g++-2.95. The first version of libstdc++-v3 appeared
 in g++-3.0.

Details

Package version:
9.2.1-19ubuntu1
Source:
gcc-9 9.2.1-19ubuntu1 source package in Ubuntu
Status:
Superseded
Component:
main
Priority:
Optional