As per formal/99-10-07, sec 3.8.4,

"It is illegal to inherit from a forward-declared valuetype whose definition has not yet been seen."

However the following code gets compiled without any errors/warnings using IDLJ compiler in merlin b30.

valuetype A; //defining a valuetype A

valuetype B : A // illegal
{
    attribute string str1;
};

valuetype A
{
    attribute string str;
};

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###@###.### 2001-08-17

- Fix verified ok
  1) with build: j2sdk-1_4_0-beta_refresh-bin-b76-solsparc-15_aug_2001
  2) with test: /tests/product/valuetypes/bugs/bug_4367729

- I am using muthu's id to verify & close the bugs since i didn't get the id yet.
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