diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h
index a28c5cab893d78418a24359bf535ae8cbe35406b..a2bed09d3c1189bfd94c0c6e19cfcf30ff81caa7 100644
--- a/arch/x86/include/asm/asm-prototypes.h
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -19,9 +19,9 @@ extern void cmpxchg8b_emu(void);
 
 #ifdef CONFIG_RETPOLINE
 
-#undef GEN
 #define GEN(reg) \
 	extern asmlinkage void __x86_indirect_thunk_ ## reg (void);
 #include <asm/GEN-for-each-reg.h>
+#undef GEN
 
 #endif /* CONFIG_RETPOLINE */
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index 18c093cb21139389efb55d44c139c2b70a3ab132..e71bfbd5faee9397d9f46f9d1d574ea767a95868 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -55,10 +55,10 @@ SYM_FUNC_END(__x86_indirect_thunk_\reg)
 #define __EXPORT_THUNK(sym)	_ASM_NOKPROBE(sym); EXPORT_SYMBOL(sym)
 #define EXPORT_THUNK(reg)	__EXPORT_THUNK(__x86_indirect_thunk_ ## reg)
 
-#undef GEN
 #define GEN(reg) THUNK reg
 #include <asm/GEN-for-each-reg.h>
-
 #undef GEN
+
 #define GEN(reg) EXPORT_THUNK(reg)
 #include <asm/GEN-for-each-reg.h>
+#undef GEN