diff --git a/src/crandom.c b/src/crandom.c
index 83999c9..4808d3e 100644
--- a/src/crandom.c
+++ b/src/crandom.c
@@ -27,10 +27,10 @@ unsigned int crandom_detect_features(void) {
     if (c & 1<<25) out |= AESNI;
     if (c & 1<<28) out |= AVX;
     if (b & 1<<5) out  |= AVX2;
+    if (c & 1<<30) out |= RDRAND;
     
     a=0x80000001; __asm__("cpuid" : "+a"(a), "=b"(b), "=c"(c), "=d"(d));
     if (c & 1<<11) out |= XOP;
-    if (c & 1<<30) out |= RDRAND;
 # endif
   
   return out;
diff --git a/src/shake.c b/src/shake.c
index 6718b0a..a5051d3 100644
--- a/src/shake.c
+++ b/src/shake.c
@@ -272,7 +272,7 @@ static void get_cpu_entropy(uint8_t *entropy, size_t len) {
     static char tested = 0, have_rdrand = 0;
     if (!tested) {
         u_int32_t a,b,c,d;
-        a=0x80000001; __asm__("cpuid" : "+a"(a), "=b"(b), "=c"(c), "=d"(d));
+        a=1; __asm__("cpuid" : "+a"(a), "=b"(b), "=c"(c), "=d"(d));
         have_rdrand = (c>>30)&1;
         tested = 1;
     }