diff --git a/src/external/libCuba/src/common/Random.c b/src/external/libCuba/src/common/Random.c
index 6d606157..d1720c5d 100644
--- a/src/external/libCuba/src/common/Random.c
+++ b/src/external/libCuba/src/common/Random.c
@@ -102,7 +102,8 @@ static inline void SobolIni(This *t)
     int inibits = -1, bit;
     for( j = powers; j; j >>= 1 ) ++inibits;
 
-    memcpy(pv, pini, inibits*sizeof *pini);
+    if( inibits > 0 )
+      memcpy(pv, pini, inibits*sizeof *pini);
     pini += 8;
 
     for( bit = inibits; bit <= nbits; ++bit ) {