diff --git a/src/system/boot/arch/x86/Jamfile b/src/system/boot/arch/x86/Jamfile
index 1a4f30cbcf..1f90ef1a3e 100644
--- a/src/system/boot/arch/x86/Jamfile
+++ b/src/system/boot/arch/x86/Jamfile
@@ -1,10 +1,24 @@
 SubDir HAIKU_TOP src system boot arch x86 ;
 
+local defines = $(DEFINES) ;
+
 local platform ;
 for platform in [ MultiBootSubDirSetup bios_ia32 efi pxe_ia32 ] {
 	on $(platform) {
+		DEFINES = $(defines) ;
 		DEFINES += _BOOT_MODE ;
 
+		if $(TARGET_BOOT_PLATFORM) = efi {
+			if $(TARGET_ARCH) = x86_64 {
+				DEFINES += BOOT_SUPPORT_ELF64 ;
+			} else {
+				DEFINES += BOOT_SUPPORT_ELF32 ;
+			}
+		} else {
+			DEFINES += BOOT_SUPPORT_ELF64 ;
+			DEFINES += BOOT_SUPPORT_ELF32 ;
+		}
+
 		local kernelArchSources =
 			arch_elf.cpp
 		;
diff --git a/src/system/kernel/arch/x86/arch_elf.cpp b/src/system/kernel/arch/x86/arch_elf.cpp
index cb1d0f2363..7e991137d3 100644
--- a/src/system/kernel/arch/x86/arch_elf.cpp
+++ b/src/system/kernel/arch/x86/arch_elf.cpp
@@ -184,10 +184,12 @@ arch_elf_relocate_rela(struct elf_image_info *image,
 }
 
 
-#endif	// !__x86_64__ || defined(ELF32_COMPAT) ||  (_BOOT_MODE && _BOOT_PLATFORM != efi)
+#endif	// !defined(__x86_64__) || defined(ELF32_COMPAT) ||
+	// (defined(_BOOT_MODE) && _BOOT_PLATFORM != efi)
 
 
-#if (defined(__x86_64__) && !defined(ELF32_COMPAT)) || defined(_BOOT_MODE)
+#if (defined(__x86_64__) && !defined(ELF32_COMPAT)) || \
+	(defined(_BOOT_MODE) && defined(BOOT_SUPPORT_ELF64))
 
 
 #ifdef _BOOT_MODE
@@ -280,4 +282,5 @@ arch_elf_relocate_rela(struct elf_image_info *image,
 }
 
 
-#endif	// (defined(__x86_64__) && !defined(ELF32_COMPAT)) || defined(_BOOT_MODE)
+#endif	// (defined(__x86_64__) && !defined(ELF32_COMPAT)) ||
+	// (defined(_BOOT_MODE) && defined(BOOT_SUPPORT_ELF64))