* warn if the first constant element of a range set expression is greater than the second one, resolves #31936

git-svn-id: trunk@38321 -

.gitattributes

@@ -14352,6 +14352,7 @@ tests/webtbf/tw3145.pp svneol=native#text/plain
 tests/webtbf/tw31465.pp svneol=native#text/pascal
 tests/webtbf/tw3183.pp svneol=native#text/plain
 tests/webtbf/tw3186.pp svneol=native#text/plain
+tests/webtbf/tw31936.pp svneol=native#text/pascal
 tests/webtbf/tw31973.pp svneol=native#text/pascal
 tests/webtbf/tw32043b.pp svneol=native#text/pascal
 tests/webtbf/tw32043c.pp svneol=native#text/pascal

compiler/msg/errore.msg

@@ -2011,6 +2011,8 @@ type_e_function_reference_kind=04123_E_Subroutine references cannot be declared
 % Subroutine references can refer to any kind of subroutine and hence do not
 % require specialisation for methods or nested subroutines.
 type_e_seg_procvardef_wrong_memory_model=04124_E_Procedure variables in that memory model do not store segment information
+type_w_empty_constant_range_set=04125_W_The first value of a set constructur range is greater then the second value, so the range describes an empty set.
+% If a set is constructed like this: \var{s:=[9..7];]}, then an empty set is generated. As this is something normally not desired, the compiler warns about it.
 % \end{description}
 #
 # Symtable

compiler/msgidx.inc

@@ -571,6 +571,7 @@ const
   type_w_instance_abstract_class=04122;
   type_e_function_reference_kind=04123;
   type_e_seg_procvardef_wrong_memory_model=04124;
+  type_w_empty_constant_range_set=04125;
   sym_e_id_not_found=05000;
   sym_f_internal_error_in_symtablestack=05001;
   sym_e_duplicate_id=05002;
@@ -1093,9 +1094,9 @@ const
   option_info=11024;
   option_help_pages=11025;
 
-  MsgTxtSize = 81190;
+  MsgTxtSize = 81312;
 
   MsgIdxMax : array[1..20] of longint=(
-    27,106,347,125,96,58,139,33,221,67,
+    27,106,347,126,96,58,139,33,221,67,
     61,20,30,1,1,1,1,1,1,1
   );

compiler/ncnv.pas

@@ -566,6 +566,8 @@ implementation
                                      inserttypeconv(p2,u8inttype);
                                    end;
 
+                                if tordconstnode(p2).value.svalue>tordconstnode(p3).value.svalue then
+                                  CGMessagePos(p2.fileinfo,type_w_empty_constant_range_set);
                                 for l:=tordconstnode(p2).value.svalue to tordconstnode(p3).value.svalue do
                                   do_set(l);
                                 p2.free;

tests/webtbf/tw31936.pp

@@ -0,0 +1,12 @@
+{ %fail }
+{ %opt=-Sew }
+var
+  I : longint;
+  Somestring : string;
+
+begin
+  Somestring:='asdf';
+  I := 1;
+  While Not (Somestring[I] in ['#'..#0]) Do Inc(I);
+end.
+