clang build VERBOSE and debug llvm

44. How to show clang build verbose message? Like the detailed build command and options?
add VERBOSE=1, like:
make VERBOSE=1

45. How to debug llvm without gdb?
add option:
 -mllvm -debug -mllvm -print-after-all -mllvm -print-before-all
This is give you enough information to start with.