[libc] [llvm] [libc] Add user defined literals to ease testing (PR #81267)

[Nick Desaulniers via llvm-commits]

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@@ -8,215 +8,188 @@
 
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/FPUtil/fpbits_str.h"
+#include "src/__support/integer_literals.h"
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nickdesaulniers wrote:

Are these some CMake changes that need to be made in addition to express this new dependency?

https://github.com/llvm/llvm-project/pull/81267