In fldbld(), check that inputFS is set.

FIXES

@@ -25,6 +25,11 @@ THIS SOFTWARE.
 This file lists all bug fixes, changes, etc., made since the AWK book
 was sent to the printers in August, 1987.
 
+June 5, 2020:
+	In fldbld(), make sure that inputFS is set before trying to
+	use it. Thanks to  Steffen Nurpmeso <steffen@sdaoden.eu>
+	for the report.
+
 May 5, 2020:
 	Fix checks for compilers that can handle noreturn. Thanks to
 	GitHub user enh-google for pointing it out. Closes Issue #79.

lib.c

@@ -332,6 +332,8 @@ void fldbld(void)	/* create fields from current record */
 	}
 	fr = fields;
 	i = 0;	/* number of fields accumulated here */
+	if (inputFS == NULL)	/* make sure we have a copy of FS */
+		savefs();
 	if (strlen(inputFS) > 1) {	/* it's a regular expression */
 		i = refldbld(r, inputFS);
 	} else if ((sep = *inputFS) == ' ') {	/* default whitespace */

main.c

@@ -22,7 +22,7 @@ ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
 THIS SOFTWARE.
 ****************************************************************/
 
-const char	*version = "version 20200515";
+const char	*version = "version 20200605";
 
 #define DEBUG
 #include <stdio.h>