diff --git a/src/alu.c b/src/alu.c
index a7c063d..6363781 100644
--- a/src/alu.c
+++ b/src/alu.c
@@ -1,5 +1,5 @@
 // ACME - a crossassembler for producing 6502/65c02/65816/65ce02 code.
-// Copyright (C) 1998-2020 Marco Baye
+// Copyright (C) 1998-2021 Marco Baye
 // Have a look at "acme.c" for further info
 //
 // Arithmetic/logic unit
diff --git a/src/tree.c b/src/tree.c
index 8b60f7f..1bc79b9 100644
--- a/src/tree.c
+++ b/src/tree.c
@@ -1,5 +1,5 @@
 // ACME - a crossassembler for producing 6502/65c02/65816/65ce02 code.
-// Copyright (C) 1998-2020 Marco Baye
+// Copyright (C) 1998-2021 Marco Baye
 // Have a look at "acme.c" for further info
 //
 // tree stuff
@@ -15,7 +15,7 @@
 // Compute hash value by exclusive ORing the node's ID string and write
 // output to struct.
 // This function is not allowed to change GlobalDynaBuf!
-hash_t make_hash(struct ronode *node) {
+static hash_t make_hash(struct ronode *node) {
 	register char		byte;
 	register const char	*read;
 	register hash_t		tmp	= 0;
@@ -200,7 +200,7 @@ static void dump_tree(struct rwnode *node, int id_number, void (*fn)(struct rwno
 		dump_tree(node->less_than_or_equal, id_number, fn, env);
 }
 
-// Calls Tree_dump_tree for each non-zero entry of the given tree table.
+// Call Tree_dump_tree for each non-zero entry of the given tree table.
 void Tree_dump_forest(struct rwnode **forest, int id_number, void (*fn)(struct rwnode *, FILE *), FILE *env)
 {
 	int	ii;
diff --git a/src/tree.h b/src/tree.h
index f171ca3..5ee9adb 100644
--- a/src/tree.h
+++ b/src/tree.h
@@ -1,5 +1,5 @@
 // ACME - a crossassembler for producing 6502/65c02/65816/65ce02 code.
-// Copyright (C) 1998-2020 Marco Baye
+// Copyright (C) 1998-2021 Marco Baye
 // Have a look at "acme.c" for further info
 //
 // tree stuff
@@ -51,7 +51,7 @@ extern int Tree_easy_scan(struct ronode *tree, void **node_body, struct dynabuf
 // create new tree item, link to tree, fill with data and store its pointer.
 // If "create" is FALSE, store NULL. Returns whether item was created.
 extern int Tree_hard_scan(struct rwnode **result, struct rwnode **forest, int id_number, boolean create);
-// Calls given function for each node of each tree of given forest.
+// Call given function for each node of each tree of given forest.
 extern void Tree_dump_forest(struct rwnode **, int id_number, void (*)(struct rwnode *, FILE *), FILE *);
 
 
diff --git a/src/version.h b/src/version.h
index eb5bfe8..c3056cc 100644
--- a/src/version.h
+++ b/src/version.h
@@ -1,5 +1,5 @@
 // ACME - a crossassembler for producing 6502/65c02/65816/65ce02 code.
-// Copyright (C) 1998-2020 Marco Baye
+// Copyright (C) 1998-2021 Marco Baye
 // Have a look at "acme.c" for further info
 //
 // version info
@@ -9,7 +9,7 @@
 
 #define RELEASE		"0.97"		// update before release	FIXME
 #define CODENAME	"Zem"		// update before release
-#define CHANGE_DATE	"27 Jan"	// update before release	FIXME
+#define CHANGE_DATE	"28 Jan"	// update before release	FIXME
 #define CHANGE_YEAR	"2021"		// update before release
 //#define HOME_PAGE	"http://home.pages.de/~mac_bacon/smorbrod/acme/"
 #define HOME_PAGE	"http://sourceforge.net/p/acme-crossass/"	// FIXME