[libc] [llvm] [libc] Provide `LIBC_TYPES_HAS_INT128` (PR #84149)

[Guillaume Chatelet via llvm-commits]

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@@ -17,6 +17,8 @@
 #include "src/__support/macros/properties/cpu_features.h"
 #include "src/__support/macros/properties/os.h"
 
+#include <stdint.h> // __SIZEOF_INT128__
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gchatelet wrote:

Not in this PR for the same reasons as https://github.com/llvm/llvm-project/pull/83441#discussion_r1517501301

https://github.com/llvm/llvm-project/pull/84149