* fix #40500: do a for-in on a string variable using low(strvar) to high(strvar) so that zero based strings are handled correctly

+ added test

compiler/nflw.pas

@@ -586,8 +586,8 @@ implementation
         addstatement(loopbodystatement,hloopbody);
 
         forloopnode:=cfornode.create(ctemprefnode.create(loopvar),
-          genintconstnode(1),
+          cinlinenode.createintern(in_low_x,false,ctemprefnode.create(stringvar)),
-          cinlinenode.create(in_length_x,false,ctemprefnode.create(stringvar)),
+          cinlinenode.create(in_high_x,false,ctemprefnode.create(stringvar)),
           loopbody,
           false);
 

tests/webtbs/tw40500.pp

@@ -0,0 +1,19 @@
+program tw40500;
+
+{$mode objfpc} {$h+} {$coperators+} {$zerobasedstrings+}
+uses
+	SysUtils;
+
+var
+	s: string;
+	c: char;
+
+begin
+	s := '';
+	for c in string('share this to instantly die') do
+		if (c >= #32) and (c <= #127) then s += c else s += '#' + IntToStr(ord(c));
+	writeln(s);
+        if s <> 'share this to instantly die' then
+                Halt(1);
+end.
+