cxx-auto is used at run time in 6 crates.

Depender (with downloads and own rev deps) cxx-auto version
5 cxx-llvm-auto ^0.0
2 cxx-llvm ^0.0
2 cxx-clang-auto ^0.0
1 cxx-clang ^0.0
1 cxx-swift-auto ^0.0
cxx-swift ^0.0