Attempt to appease msc buildbot

It was timing out on this test, but for reasons unrelated to the
specific bug it was testing for. Randomly breaking in gdb with `clang
-target i686-windows -fmsc-version=1700` reveals *many* frames from
MicrosoftCXXNameMangler. So, it would seem that some caching is needed
there, as well...

Fingers crossed that specifying a triple is sufficient to work around
this.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@310444 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGenCXX/pr29160.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++11 %s -o /dev/null -S
+// RUN: %clang_cc1 -std=c++11 -triple i686-linux %s -o /dev/null -S
 //
 // This test's failure mode is running ~forever. (For some value of "forever"
 // that's greater than 25 minutes on my machine)