diff --git a/boot/freeldr/freeldr/freeldr_i386.msvc.lds b/boot/freeldr/freeldr/freeldr_i386.msvc.lds
index bcfc19204e3b3..53e00ba8af3be 100644
--- a/boot/freeldr/freeldr/freeldr_i386.msvc.lds
+++ b/boot/freeldr/freeldr/freeldr_i386.msvc.lds
@@ -44,6 +44,47 @@
 
 #include <asm.inc>
 
+
+#ifdef _M_AMD64
+_TEXT SEGMENT 'CODE'
+
+/*
+__declspec(noreturn) __forceinline
+void __fastfail(unsigned int Code) // __cdecl
+*/
+PUBLIC __fastfail
+__fastfail:
+
+#ifdef _M_IX86 // _X86_
+    push ebp
+    mov  ebp, esp
+    mov  ecx, [ebp+8/*Code*/]
+#elif defined(_M_AMD64)
+    /* First argument already in rcx */
+#else
+#error Unsupported architecture
+#endif
+
+    int HEX(29)
+
+/* Never return */
+    cli
+die:
+    hlt
+    jmp die
+
+#ifdef _M_IX86 // _X86_
+    pop ebp
+#elif !defined(_M_AMD64)
+#error Unsupported architecture
+#endif
+    ret
+
+_TEXT ENDS
+#endif // _M_AMD64
+
+
+
 /*
 #pragma bss_seg(".bss")
 // __declspec(allocate(".bss"))
diff --git a/sdk/include/asm/asm.inc b/sdk/include/asm/asm.inc
index 7b3df60e6b127..0320b209d48d3 100644
--- a/sdk/include/asm/asm.inc
+++ b/sdk/include/asm/asm.inc
@@ -9,6 +9,9 @@
 #ifndef __ASM_INC__
 #define __ASM_INC__
 
+// /* Makes "x" a global variable or label */
+// #define EXTERN(x)    .global x; x:
+
 /*
  * Common definitions for the FPO macro.
  * See https://docs.microsoft.com/en-us/windows/desktop/api/winnt/ns-winnt-_fpo_data
@@ -99,7 +102,9 @@ ENDM
 
 .code32 MACRO
     .code
+#ifdef _M_IX86
     .586P
+#endif
 ENDM
 
 .code16 MACRO
diff --git a/sdk/include/crt/msc/intrin.h b/sdk/include/crt/msc/intrin.h
index 5fd3001917458..a1a8d9b6f1057 100644
--- a/sdk/include/crt/msc/intrin.h
+++ b/sdk/include/crt/msc/intrin.h
@@ -279,6 +279,7 @@ void __fastfail(unsigned int Code)
     }
 }
 #else
+__declspec(noreturn) __forceinline
 void __fastfail(unsigned int Code);
 #endif // defined(_M_IX86)
 #endif
@@ -356,6 +357,7 @@ void _sgdt(void *Destination)
     }
 }
 #else
+__forceinline
 void _sgdt(void *Destination);
 #endif // defined(_M_IX86)
 #endif