Add ENABLE_COVERAGE, for building a +Coverage (gcov) configuration.
 - Required some extra makefile tweaks to introduce a new flag var
   which only goes to compile/link tools but not the relink step,
   otherwise we get a copy of libgcov in the relinked .o files.

 - No configure magic for this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66945 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed