Improve dependency file support.
 - Rip out various bits of logic from clang-cc's dependency file gen,
   force driver to provide instead.

 - -MD output now goes to proper location
<rdar://problem/6723948> clang -MD puts dep file in /tmp with wrong name

 - -M and -MM still don't work correctly.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68022 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Frontend/dependency-gen.c b/test/Frontend/dependency-gen.c
index ea95e06..a9ee637 100644
--- a/test/Frontend/dependency-gen.c
+++ b/test/Frontend/dependency-gen.c
@@ -1,5 +1,5 @@
-
 // rdar://6533411
-// RUN: clang-cc -MD -MF %t.d -x c /dev/null
+// RUN: clang -MD -MF %t.d -c -x c -o %t.o /dev/null && 
 
-
+// RUN: grep '.*dependency-gen.c.out.tmp.o:' %t.d
+// RUN: grep '/dev/null' %t.d