[PR] match wide local variable instruction length to dumped bytes [commons-bcel]

["rootvector2 (via GitHub)" <gi...@apache.org>]

rootvector2 opened a new pull request, #525:
URL: https://github.com/apache/commons-bcel/pull/525

   `LocalVariableInstruction.initFromFile` hardcodes length 4 for any `wide`-prefixed load or store, but `dump()` writes the `wide` prefix only when the index is above `Const.MAX_BYTE`. A `wide iload 5` is legal bytecode whose index fits in a byte, so it parses with `getLength()` 4 while `dump()` emits 2 bytes. I hit this auditing `wide` handling against `RET` and `IINC`, which persist the parsed flag and keep the two in sync.
   
   `InstructionList.setPositions` accumulates `getLength()`, so rebuilding a parsed method that carries one of these instructions shifts every following instruction 2 bytes and corrupts the branch offsets that span it. Deriving the parsed length from the same `wide()` test `dump()` already uses keeps length and emitted bytes in agreement, leaving the compact and non-wide paths untouched.
   
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Re: [PR] Match wide local variable instruction length to dumped bytes [commons-bcel]

["garydgregory (via GitHub)" <gi...@apache.org>]

garydgregory merged PR #525:
URL: https://github.com/apache/commons-bcel/pull/525


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