[compiler-rt] [builtins] Support building the 128-bit float functions on x86 (PR #68132)

[Alexander Richardson via llvm-commits]

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@@ -6,7 +6,9 @@
 #include <stdio.h>
 #include "fp_lib.h"
 
-#if defined(CRT_HAS_TF_MODE)
+// TODO: This test currently only works if long double is the same as fp_t.
+// On x86_64 we get undefined references to __trunctfxf2 and __extendxftf2
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arichardson wrote:

I can drop this part of the diff if your change lands first.

https://github.com/llvm/llvm-project/pull/68132