[clang] [llvm] Fix c-index-test when compiling llvm to a dylib (PR #219092)

[Oliver Hunt via llvm-commits]

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@@ -328,6 +330,74 @@ TimerGroup::~TimerGroup() {
   unlink();
 }
 
+// ***REVIEWER***: I really don't know if this is warranted? I'm unaware of any
+// major environment where the stack grows up these days, but there's a
+// difference between me being unaware of such, and it not actually existing or
+// being a supported host platform.
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ojhunt wrote:

Or @AaronBallman what is your thought on whether I need to care about upward growing stacks?

https://github.com/llvm/llvm-project/pull/219092