[compiler-rt] [compiler-rt][builtins][test][darwin] Fix some compiler-rt builtins tests on Apple platforms (PR #207895)

[Andrew Haberlandt via llvm-commits]

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@@ -63,11 +63,13 @@ int main() {
     defined(__i386__) || defined(__x86_64__)
 // Skip these tests on Windows because the UCRT scalbn function always behaves
 // as if the default rounding mode is set (FE_TONEAREST).
+// Also skip on Apple because the libm scalbn flushes underflow to zero
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ndrewh wrote:

I see... since this is potentially a OS bug, it might be better to XFAIL based on OS version, so that we only disable the test on OS version where it is broken. Assuming you don't want to try to do that, I'd suggest just ignoring it. If CI updates to a OS that is broken, one of us will surely get pinged to implement the proper XFAIL.

https://github.com/llvm/llvm-project/pull/207895