[compiler-rt] [libunwind] [AArch64] Fix nofp regressions in compiler-rt and libunwind (PR #111235)

[Oliver Stannard via cfe-commits]

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@@ -1,5 +1,20 @@
 #include <stddef.h>
 
+#if __ARM_FP == 0
+// WARNING: When building the scalar versions of these functions you need to
+// use the compiler flag "-mllvm -disable-loop-idiom-all" to prevent clang
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ostannard wrote:

I think `-fno-builtin-memcpy` would be a better option to recommend here, as that's a user-facing option, while the  `-mllvm` options are internal options, mostly intended for LLVM developers.

Could this be added to the CMakeLists.txt for this file?

https://github.com/llvm/llvm-project/pull/111235