Marked with ATTRIBUTE_USED so that clang doesn't complain.

llvm-svn: 111383
diff --git a/llvm/lib/Target/X86/X86FloatingPoint.cpp b/llvm/lib/Target/X86/X86FloatingPoint.cpp
index 4bf7cdb..e6ebf66 100644
--- a/llvm/lib/Target/X86/X86FloatingPoint.cpp
+++ b/llvm/lib/Target/X86/X86FloatingPoint.cpp
@@ -572,7 +572,7 @@
     friend bool operator<(const TableEntry &TE, unsigned V) {
       return TE.from < V;
     }
-    friend bool operator<(unsigned V, const TableEntry &TE) {
+    friend bool ATTRIBUTE_USED operator<(unsigned V, const TableEntry &TE) {
       return V < TE.from;
     }
   };