diff --git a/crypto/ec/curve25519.c b/crypto/ec/curve25519.c
index d1c725fa39749144626d3d2095055f6f7b698b85..f32fc04d6ae9e5ce222ea19fc95c7f22c4f12b19 100644
--- a/crypto/ec/curve25519.c
+++ b/crypto/ec/curve25519.c
@@ -12,6 +12,7 @@
 #include <openssl/sha.h>
 
 #if !defined(PEDANTIC) && \
+    !defined(__sparc__) && \
     (defined(__SIZEOF_INT128__) && __SIZEOF_INT128__==16)
 /*
  * Base 2^51 implementation.