diff --git a/src/ext/ed25519/donna/ed25519-donna-portable.h b/src/ext/ed25519/donna/ed25519-donna-portable.h
index 1cd644c003..9c9c55577c 100644
--- a/src/ext/ed25519/donna/ed25519-donna-portable.h
+++ b/src/ext/ed25519/donna/ed25519-donna-portable.h
@@ -144,6 +144,16 @@ static inline void U64TO8_LE(unsigned char *p, const uint64_t v) {
 	#endif
 #endif
 
+/* Tor: Force enable SSE2 on 32 bit x86 systems if the compile target
+ * architecture supports it.  This is not done on x86-64 as the non-SSE2
+ * code benchmarks better, at least on Haswell.
+ */
+#if defined(__SSE2__) /* && !defined(CPU_X86_64) */
+	/* undef in case it's manually specified... */
+	#undef ED25519_SSE2
+	#define ED25519_SSE2
+#endif
+
 /* Tor: GCC's Stack Protector freaks out and produces variable length
  * buffer warnings when alignment is requested that is greater than
  * STACK_BOUNDARY (x86 has special code to deal with this for SSE2).
@@ -158,16 +168,6 @@ static inline void U64TO8_LE(unsigned char *p, const uint64_t v) {
 	#define ALIGN(x)
 #endif
 
-/* Tor: Force enable SSE2 on 32 bit x86 systems if the compile target
- * architecture supports it.  This is not done on x86-64 as the non-SSE2
- * code benchmarks better, at least on Haswell.
- */
-#if defined(__SSE2__) && !defined(CPU_X86_64)
-	/* undef in case it's manually specified... */
-	#undef ED25519_SSE2
-	#define ED25519_SSE2
-#endif
-
 #include <stdlib.h>
 #include <string.h>