[libc] [llvm] [libc][stdfix] Add round functions for fixed point types. (PR #81994)

[via llvm-commits]

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@@ -17,4 +17,5 @@ add_header_library(
     libc.include.llvm-libc-macros.stdfix_macros
     libc.src.__support.macros.attributes
     libc.src.__support.macros.optimization
+    libc.src.__support.CPP.bit
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lntue wrote:

Done.

https://github.com/llvm/llvm-project/pull/81994