diff --git a/algorithm/fresh.c b/algorithm/fresh.c
index a5ef6619..26c6bbd1 100644
--- a/algorithm/fresh.c
+++ b/algorithm/fresh.c
@@ -49,7 +49,7 @@ typedef struct {
   sph_echo512_context     echo2;
 } FreshHash_context_holder;
 
-FreshHash_context_holder base_contexts;
+static FreshHash_context_holder base_contexts;
 
 void init_freshHash_contexts()
 {
diff --git a/algorithm/qubitcoin.c b/algorithm/qubitcoin.c
index efbfa913..00c503d7 100644
--- a/algorithm/qubitcoin.c
+++ b/algorithm/qubitcoin.c
@@ -50,7 +50,7 @@ typedef struct {
     sph_echo512_context     echo1;
 } Qhash_context_holder;
 
-Qhash_context_holder base_contexts;
+static Qhash_context_holder base_contexts;
 
 
 void init_Qhash_contexts()
diff --git a/algorithm/whirlcoin.c b/algorithm/whirlcoin.c
index 211aeaf3..8d843ddb 100644
--- a/algorithm/whirlcoin.c
+++ b/algorithm/whirlcoin.c
@@ -44,7 +44,7 @@ typedef struct {
   sph_whirlpool1_context whirlpool4;
 } Whash_context_holder;
 
-Whash_context_holder base_contexts;
+static Whash_context_holder base_contexts;
 
 
 void init_whirlcoin_hash_contexts()
@@ -157,4 +157,4 @@ bool scanhash_whirlcoin(struct thr_info *thr, const unsigned char __maybe_unused
 
   return ret;
 }
-*/
\ No newline at end of file
+*/
diff --git a/miner.h b/miner.h
index 0b0bceee..b7c3ffb8 100644
--- a/miner.h
+++ b/miner.h
@@ -246,7 +246,7 @@ enum drv_driver {
 
 /* Use DRIVER_PARSE_COMMANDS to generate extern device_drv prototypes */
 #ifndef _MSC_VER
-DRIVER_PARSE_COMMANDS(DRIVER_PROTOTYPE)
+extern DRIVER_PARSE_COMMANDS(DRIVER_PROTOTYPE)
 #endif
 
 // helper to check for empty or NULL strings