* Further improvement for r40180:

    An uninitialized function Result of a managed type needs special handling.
    When passing it as a var parameter a warning need to be emitted, since a user
    may expect Result to be empty (nil) by default as it happens with local vars
    of a managed type. But this is not true for Result and may lead to serious issues.

    The only exception is SetLength(Result, ?) for a string Result. A user always
    expects undefined contents of the string after calling SetLength(). In such
    case a hint need to be emitted.
+ Tests for this.

git-svn-id: https://svn.freepascal.org/svn/fpc/trunk@40216 3ad0048d-3df7-0310-abae-a5850022a9f2

1 files changed, 64 insertions, 0 deletions

diff --git a/tests/tbs/tb0653.pp b/tests/tbs/tb0653.pp
new file mode 100644
index 0000000000..d821065090
--- /dev/null
+++ b/tests/tbs/tb0653.pp
@@ -0,0 +1,64 @@
+{ %norun }
+{ %opt=-Sewn -vwn -O- }
+
+{
+  Test for correct emitting of warnings/hints for uninitialized variables of management types
+  See also tbf/tb0258.pp
+}
+
+// Only hints about uninitialized managed variables must be issued for this code
+
+{$mode objfpc}
+
+type
+  TLongArray = array of longint;
+
+procedure p;
+var
+  a : TLongArray;
+  s: ansistring;
+begin
+  setlength(a,100);  // hint for local var
+  setlength(s,100);  // hint for local var
+  a[1]:=1;
+  writeln(a[1]);
+  s[1]:='a';
+  writeln(s[1]);
+end;
+
+procedure svar(var s: ansistring; len: longint);
+begin
+  setlength(s,len);
+end;
+
+procedure avar(var a: TLongArray; len: longint);
+begin
+  setlength(a,len);
+end;
+
+procedure p2;
+var
+  a : TLongArray;
+  s: ansistring;
+begin
+  avar(a,100);  // hint for local var
+  svar(s,100);  // hint for local var
+  a[1]:=1;
+  writeln(a[1]);
+  s[1]:='a';
+  writeln(s[1]);
+end;
+
+function f2: ansistring;
+begin
+  // Hint for the ansistring Result, since all contents of the Result
+  // after calling SetLength() is expected to be undefined.
+  setlength(Result,1);
+  Result[1]:='a';
+end;
+
+begin
+  p;
+  p2;
+  f2;
+end.