Driver: Add -[no-]integrated-as for clang.
 - Requires backend support, which only exists for i386--darwin currently.

No 'as' required:
--
ddunbar@ozzy:tmp$ cat t.c
int main() { return 42; }
ddunbar@ozzy:tmp$ clang -m32 -integrated-as t.c


ddunbar@ozzy:tmp$ ./a.out; echo $?
42
ddunbar@ozzy:tmp$
--

The random extra whitespace is how you know its working! :)

llvm-svn: 95194
diff --git a/clang/lib/Driver/Tools.h b/clang/lib/Driver/Tools.h
index 572c7f4..db59641 100644
--- a/clang/lib/Driver/Tools.h
+++ b/clang/lib/Driver/Tools.h
@@ -41,6 +41,7 @@
 
     virtual bool acceptsPipedInput() const { return true; }
     virtual bool canPipeOutput() const { return true; }
+    virtual bool hasIntegratedAssembler() const { return true; }
     virtual bool hasIntegratedCPP() const { return true; }
 
     virtual void ConstructJob(Compilation &C, const JobAction &JA,