Index: sys/contrib/zstd/lib/compress/zstd_compress_internal.h
===================================================================
--- sys/contrib/zstd/lib/compress/zstd_compress_internal.h
+++ sys/contrib/zstd/lib/compress/zstd_compress_internal.h
@@ -689,6 +689,7 @@
 }
 
 
+#if (DEBUGLEVEL>=2)
 /* debug functions */
 
 MEM_STATIC double ZSTD_fWeight(U32 rawStat)
@@ -714,6 +715,7 @@
                 u, table[u], ZSTD_fWeight(sum) - ZSTD_fWeight(table[u]) );
     }
 }
+#endif
 
 #if defined (__cplusplus)
 }
Index: sys/contrib/zstd/lib/compress/zstd_opt.c
===================================================================
--- sys/contrib/zstd/lib/compress/zstd_opt.c
+++ sys/contrib/zstd/lib/compress/zstd_opt.c
@@ -52,11 +52,13 @@
     return weight;
 }
 
+#if (DEBUGLEVEL>=2)
 /* debugging function, @return price in bytes */
 MEM_STATIC double ZSTD_fCost(U32 price)
 {
     return (double)price / (BITCOST_MULTIPLIER*8);
 }
+#endif
 
 static void ZSTD_setBasePrices(optState_t* optPtr, int optLevel)
 {