diff --git a/GUI/xephem/compiler.c b/GUI/xephem/compiler.c
index 63a0065..16bf565 100644
--- a/GUI/xephem/compiler.c
+++ b/GUI/xephem/compiler.c
@@ -208,7 +208,7 @@ next_token ()
 {
 	static char toomv[] = "More than %d variables";
 	static char toomc[] = "More than %d constants";
-	static char badop[] = "Illegal operator";
+	static const char badop[] = "Illegal operator";
 	int tok = ERR;	/* just something illegal */
 	char c;
 
diff --git a/GUI/xephem/obslog.c b/GUI/xephem/obslog.c
index e3912e2..7deb5a6 100644
--- a/GUI/xephem/obslog.c
+++ b/GUI/xephem/obslog.c
@@ -915,7 +915,7 @@ ol_writeLB()
 	fprintf (fp, "    </%s>\n", lbetag);
 
 	/* finished */
-	fprintf (fp, cltag);
+	fprintf (fp, "%s", cltag);
 	xe_msg (1, "Added new log entry");
 	fclose (fp);
 }
diff --git a/GUI/xephem/tools/indi/compiler.c b/GUI/xephem/tools/indi/compiler.c
index 2e16d93..736f2a1 100644
--- a/GUI/xephem/tools/indi/compiler.c
+++ b/GUI/xephem/tools/indi/compiler.c
@@ -268,7 +268,7 @@ next_token ()
 {
 	static char toomv[] = "More than %d variables";
 	static char toomc[] = "More than %d constants";
-	static char badop[] = "Illegal operator";
+	static const char badop[] = "Illegal operator";
 	int tok = ERR;	/* just something illegal */
 	char c;
 
diff --git a/GUI/xephem/tools/lx200xed/lx200xed.c b/GUI/xephem/tools/lx200xed/lx200xed.c
index 34bdb33..4c6e5b0 100644
--- a/GUI/xephem/tools/lx200xed/lx200xed.c
+++ b/GUI/xephem/tools/lx200xed/lx200xed.c
@@ -657,7 +657,7 @@ trace(int iLevel, char *szpFormat, char *szpArg)
 {
    if(iLevel<=config.iTrace) {
       if(szpArg==NULL)
-	printf(szpFormat);
+	printf("%s", szpFormat);
       else
 	printf(szpFormat,szpArg);
    }