diff --git a/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h b/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h
index c4951003c3af4..cb144e1afb21f 100644
--- a/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h
+++ b/Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h
@@ -62,7 +62,6 @@
 #include "WebAssemblyModuleRecord.h"
 #include <wtf/BooleanLattice.h>
 #include <wtf/CheckedArithmetic.h>
-#include <wtf/ForkExtras.h>
 
 namespace JSC { namespace DFG {
 
diff --git a/Source/JavaScriptCore/runtime/JSObjectInlines.h b/Source/JavaScriptCore/runtime/JSObjectInlines.h
index 3c8c2f0884f3d..3f6988545cb03 100644
--- a/Source/JavaScriptCore/runtime/JSObjectInlines.h
+++ b/Source/JavaScriptCore/runtime/JSObjectInlines.h
@@ -37,7 +37,6 @@
 #include "MegamorphicCache.h"
 #include "StructureInlines.h"
 #include "TypedArrayType.h"
-#include <wtf/ForkExtras.h>
 
 namespace JSC {
 
diff --git a/Source/WTF/wtf/Float16.h b/Source/WTF/wtf/Float16.h
index 8fbfd7eef99e6..e003005a6a5f7 100644
--- a/Source/WTF/wtf/Float16.h
+++ b/Source/WTF/wtf/Float16.h
@@ -56,7 +56,7 @@ namespace WTF {
  */
 constexpr float convertFloat16ToFloat32(uint16_t h)
 {
-#if (CPU(ARM64) || CPU(X86_64)) && defined(__FLT16_MANT_DIG__)
+#if HAVE(FLOAT16)
     return static_cast<float>(__bit_cast<_Float16>(h));
 #else
 
@@ -178,7 +178,7 @@ constexpr double convertFloat16ToFloat64(uint16_t h)
  */
 constexpr uint16_t convertFloat32ToFloat16(float f)
 {
-#if (CPU(ARM64) || CPU(X86_64)) && defined(__FLT16_MANT_DIG__)
+#if HAVE(FLOAT16)
     return __bit_cast<uint16_t>(static_cast<_Float16>(f));
 #else
     const float scale_to_inf = 0x1.0p+112f; // 0x77800000
@@ -206,7 +206,7 @@ constexpr uint16_t convertFloat32ToFloat16(float f)
 // Adopted from V8's DoubleToFloat16, which adopted from https://gist.github.com/rygorous/2156668.
 constexpr uint16_t convertFloat64ToFloat16(double value)
 {
-#if (CPU(ARM64) || CPU(X86_64)) && defined(__FLT16_MANT_DIG__)
+#if HAVE(FLOAT16)
     return __bit_cast<uint16_t>(static_cast<_Float16>(value));
 #else
     // uint64_t constants prefixed with kFP64 are bit patterns of doubles.
@@ -286,7 +286,7 @@ constexpr uint16_t convertFloat64ToFloat16(double value)
 #endif
 }
 
-#if (CPU(ARM64) || CPU(X86_64)) && defined(__FLT16_MANT_DIG__)
+#if HAVE(FLOAT16)
 class Float16 {
 public:
     constexpr Float16() = default;
diff --git a/Source/WTF/wtf/ForkExtras.h b/Source/WTF/wtf/ForkExtras.h
index 76cde51188d50..108f92b3cc459 100644
--- a/Source/WTF/wtf/ForkExtras.h
+++ b/Source/WTF/wtf/ForkExtras.h
@@ -25,31 +25,3 @@ typedef struct jsstring_iterator {
 #ifdef __cplusplus
 }
 #endif
-
-#if CPU(X86_64)
-
-#ifndef __extendhfsf2
-#if defined(__FLT16_MANT_DIG__)
-extern "C" float __extendhfsf2(_Float16 a);
-#else
-extern "C" float __extendhfsf2(uint16_t a);
-#endif
-#endif
-
-#ifndef __truncdfhf2
-#if defined(__FLT16_MANT_DIG__)
-extern "C" _Float16 __truncdfhf2(double a);
-#else
-extern "C" uint16_t __truncdfhf2(double a);
-#endif
-#endif
-
-#ifndef __truncsfhf2
-#if defined(__FLT16_MANT_DIG__)
-extern "C" _Float16 __truncsfhf2(float a);
-#else
-extern "C" uint16_t __truncsfhf2(float a);
-#endif
-#endif
-
-#endif
diff --git a/Source/WTF/wtf/StdLibExtras.h b/Source/WTF/wtf/StdLibExtras.h
index 917f2f8691d9c..d4df7fbc4c86c 100644
--- a/Source/WTF/wtf/StdLibExtras.h
+++ b/Source/WTF/wtf/StdLibExtras.h
@@ -39,7 +39,6 @@
 #include <wtf/GetPtr.h>
 #include <wtf/TypeCasts.h>
 #include <bit>
-#include <wtf/ForkExtras.h>
 
 #if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
 #define __bit_cast std::bit_cast