start of a filename, not a filename+length.  All clients can produce a
null terminated name, and the system api's require null terminated 
strings anyway.

llvm-svn: 49041

llvm-svn: 47695

first commit of new LTO system.  It is not hooked up in the llvm/tools/Makefile, so no one will build it be default yet

llvm-svn: 47621