/usr/lib/llvm-3.5/include/lldb/Expression/ is in lldb-3.5-dev 1:3.5~svn201651-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/llvm-3.5/include/lldb/Expression/ASTDumper.h
/usr/lib/llvm-3.5/include/lldb/Expression/ASTResultSynthesizer.h
/usr/lib/llvm-3.5/include/lldb/Expression/ASTStructExtractor.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangASTSource.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangExpression.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangExpressionDeclMap.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangExpressionParser.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangExpressionVariable.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangFunction.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangPersistentVariables.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangUserExpression.h
/usr/lib/llvm-3.5/include/lldb/Expression/ClangUtilityFunction.h
/usr/lib/llvm-3.5/include/lldb/Expression/DWARFExpression.h
/usr/lib/llvm-3.5/include/lldb/Expression/ExpressionSourceCode.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRDynamicChecks.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRExecutionUnit.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRForTarget.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRInterpreter.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRMemoryMap.h
/usr/lib/llvm-3.5/include/lldb/Expression/IRToDWARF.h
/usr/lib/llvm-3.5/include/lldb/Expression/Materializer.h