diff --git a/clang/lib/AST/Interp/Interp.cpp b/clang/lib/AST/Interp/Interp.cpp
index c3503f4a07895..cf9e5b8ea6bd2 100644
--- a/clang/lib/AST/Interp/Interp.cpp
+++ b/clang/lib/AST/Interp/Interp.cpp
@@ -496,14 +496,6 @@ bool CheckFloatResult(InterpState &S, CodePtr OpPC, APFloat::opStatus Status) {
   return true;
 }
 
-bool CastFP(InterpState &S, CodePtr OpPC, const llvm::fltSemantics *Sem,
-            llvm::RoundingMode RM) {
-  Floating F = S.Stk.pop<Floating>();
-  Floating Result = F.toSemantics(Sem, RM);
-  S.Stk.push<Floating>(Result);
-  return true;
-}
-
 bool Interpret(InterpState &S, APValue &Result) {
   // The current stack frame when we started Interpret().
   // This is being used by the ops to determine wheter
diff --git a/clang/lib/AST/Interp/Interp.h b/clang/lib/AST/Interp/Interp.h
index f179c0486bdbd..d70b732f6fd86 100644
--- a/clang/lib/AST/Interp/Interp.h
+++ b/clang/lib/AST/Interp/Interp.h
@@ -1421,9 +1421,13 @@ template <PrimType TIn, PrimType TOut> bool Cast(InterpState &S, CodePtr OpPC) {
 
 /// 1) Pops a Floating from the stack.
 /// 2) Pushes a new floating on the stack that uses the given semantics.
-/// Not templated, so implemented in Interp.cpp.
-bool CastFP(InterpState &S, CodePtr OpPC, const llvm::fltSemantics *Sem,
-            llvm::RoundingMode RM);
+inline bool CastFP(InterpState &S, CodePtr OpPC, const llvm::fltSemantics *Sem,
+            llvm::RoundingMode RM) {
+  Floating F = S.Stk.pop<Floating>();
+  Floating Result = F.toSemantics(Sem, RM);
+  S.Stk.push<Floating>(Result);
+  return true;
+}
 
 template <PrimType Name, class T = typename PrimConv<Name>::T>
 bool CastIntegralFloating(InterpState &S, CodePtr OpPC,