/usr/lib/llvm-2.9/include/llvm-c/ is in llvm-2.9-dev 2.9+dfsg-3ubuntu4.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/llvm-2.9/include/llvm-c/Analysis.h
/usr/lib/llvm-2.9/include/llvm-c/BitReader.h
/usr/lib/llvm-2.9/include/llvm-c/BitWriter.h
/usr/lib/llvm-2.9/include/llvm-c/Core.h
/usr/lib/llvm-2.9/include/llvm-c/EnhancedDisassembly.h
/usr/lib/llvm-2.9/include/llvm-c/ExecutionEngine.h
/usr/lib/llvm-2.9/include/llvm-c/Initialization.h
/usr/lib/llvm-2.9/include/llvm-c/LinkTimeOptimizer.h
/usr/lib/llvm-2.9/include/llvm-c/Target.h
/usr/lib/llvm-2.9/include/llvm-c/Transforms/
/usr/lib/llvm-2.9/include/llvm-c/Transforms/IPO.h
/usr/lib/llvm-2.9/include/llvm-c/Transforms/Scalar.h
/usr/lib/llvm-2.9/include/llvm-c/lto.h