libclang-9-dev 1:9.0.1-12 (riscv64 binary) in ubuntu focal

 Clang project is a C, C++, Objective C and Objective C++ front-end
 based on the LLVM compiler. Its goal is to offer a replacement to the
 GNU Compiler Collection (GCC).
 .
 Clang implements all of the ISO C++ 1998, 11 and 14 standards and also
 provides most of the support of C++17.
 .
 This package contains the Clang headers to develop extensions over
 libclang1-9.