我一直在尝试使用dub run较新的版本，但它不起作用，它只是重建旧版本。
$ dub run dpp@0.3.4
Fetching dpp 0.3.4...
Building package dpp in /Users/james/.dub/packages/dpp-0.3.1/dpp/
Performing "debug" build using /Library/D/dmd/bin/dmd for x86_64.
libclang 0.1.8: building configuration "library"...
sumtype 0.7.1: building configuration "library"...
dpp 0.3.1: building configuration "executable"...
Linking...
ld: warning: directory not found for option '-L/usr/lib/llvm-6.0/lib'
ld: warning: directory not found for option '-L/usr/lib/llvm-3.9/lib'
Running ../../../../.dub/packages/dpp-0.3.1/dpp/bin/d++
Error: No .dpp input file specified
Usage: d++ [options] [D compiler options] <filename.dpp> [D compiler args]
Program exited with code 1
dub cache-clean也不能解决问题。