diff --git a/source/find.c b/source/find.c
index 2cfc27e..0122300 100644
--- a/source/find.c
+++ b/source/find.c
@@ -672,6 +672,12 @@ char *findinclude(const char *pattern) {
 
 /* initialize */
 int findinit(const char *pattern_) {
+
+	if (pattern_ == NULL
+    ||  pattern_[0] == '\0') {
+		return NOTSYMBOL;
+	}
+
 	char		 *pattern = strdup(pattern_);
 	int			  r		  = NOERROR;
 	char		  buf[PATLEN + 3];
@@ -685,8 +691,11 @@ int findinit(const char *pattern_) {
 
 	isregexp_valid = false;
 
+	/* Pattern length */
+	size_t pattlen = strlen(pattern);
+
 	/* remove trailing white space */
-	for(s = pattern + strlen(pattern) - 1; isspace((unsigned char)*s); --s) {
+	for(s = pattern + (pattlen - 1); isspace((unsigned char)*s); --s) {
 		*s = '\0';
 	}
 
@@ -772,6 +781,7 @@ int findinit(const char *pattern_) {
 	}
 
 end:
+	free(pattern);
 	return r;
 }