fixed a parser bug in awk.

- handling of idiv operators
- tokenization of /=/ as a regular expression
- calling QSE_AWK_FREEREX to free compiled regular expressions.
switched to a new regular expression handler.

qse/regress/awk/lang-042.awk

@@ -0,0 +1,18 @@
+BEGIN { 
+	print //; 
+	print /=/; 
+	print /.*/;
+
+	a=5; a /= 10; print a;
+
+	for (IGNORECASE=0; IGNORECASE<=1;IGNORECASE++)
+	{
+		print "IGNORECASE=", IGNORECASE;
+		print "abc" ~ /^[[:upper:]]+$/; 
+		print "abc" ~ /^[[:lower:]]+$/; 
+		print "ABC" ~ /^[[:upper:]]+$/; 
+		print "ABC" ~ /^[[:lower:]]+$/; 
+		print "AbC" ~ /^[[:upper:]]+$/; 
+		print "aBc" ~ /^[[:lower:]]+$/; 
+	}
+}

qse/regress/awk/regress.out

@@ -2046,6 +2046,46 @@ BEGIN {
 }
 
 2010
+--------------------------------------------------------------------------------
+ ../../cmd/awk/.libs/qseawk --newline=on -o- -f lang-042.awk  </dev/stdin 2>&1 
+--------------------------------------------------------------------------------
+BEGIN {
+	print //;
+	print /=/;
+	print /.*/;
+	a = 5;
+	a /= 10;
+	print a;
+	for (IGNORECASE = 0; (IGNORECASE <= 1); (IGNORECASE)++)
+	{
+		print "IGNORECASE=",IGNORECASE;
+		print ("abc" ~ /^[[:upper:]]+$/);
+		print ("abc" ~ /^[[:lower:]]+$/);
+		print ("ABC" ~ /^[[:upper:]]+$/);
+		print ("ABC" ~ /^[[:lower:]]+$/);
+		print ("AbC" ~ /^[[:upper:]]+$/);
+		print ("aBc" ~ /^[[:lower:]]+$/);
+	}
+}
+
+1
+0
+1
+0.5
+IGNORECASE= 0
+0
+1
+1
+0
+0
+0
+IGNORECASE= 1
+1
+1
+1
+1
+1
+1
 --------------------------------------------------------------------------------
  ../../cmd/awk/.libs/qseawk  -f quicksort.awk quicksort.dat </dev/stdin 2>&1 
 --------------------------------------------------------------------------------

qse/regress/awk/regress.sh

@@ -152,6 +152,7 @@ PROGS="
 	lang-039.awk///--newline=on -o-
 	lang-040.awk///--newline=on -o-
 	lang-041.awk///--newline=on -o-
+	lang-042.awk///--newline=on -o-
 
 	quicksort.awk/quicksort.dat//
 	quicksort2.awk/quicksort2.dat//