diff --git a/golded3/geline.cpp b/golded3/geline.cpp
index 8aecdc4..c40be70 100644
--- a/golded3/geline.cpp
+++ b/golded3/geline.cpp
@@ -2929,7 +2929,7 @@ Line* LastLine(Line* line) {
 
 //  ------------------------------------------------------------------
 
-Line* AddLine(Line* line, char* buf, int where) {
+Line* AddLine(Line* line, const char* buf, int where) {
 
   Line* newline = new Line(buf);
   throw_xnew(newline);
@@ -2942,7 +2942,7 @@ Line* AddLine(Line* line, char* buf, int where) {
 
 //  ------------------------------------------------------------------
 
-Line* AddLine(Line* line, char* buf) {
+Line* AddLine(Line* line, const char* buf) {
 
   return AddLine(line, buf, DIR_BELOW);
 }
diff --git a/goldlib/gmb3/gmo_msg.h b/goldlib/gmb3/gmo_msg.h
index af8f5a3..8e1defe 100644
--- a/goldlib/gmb3/gmo_msg.h
+++ b/goldlib/gmb3/gmo_msg.h
@@ -171,7 +171,7 @@ public:
 //  ------------------------------------------------------------------
 
 Line* AddLineF(Line*& line, const char* format, ...) __attribute__ ((format (printf, 2, 3)));
-Line* AddLine(Line* line, char* buf);
+Line* AddLine(Line* line, const char* buf);
 Line* AddHexdump(Line*& line, void* data, size_t datalen);