[Python-Dev] Is core dump always a bug? Advice requested (original) (raw)

Skip Montanaro skip at pobox.com
Thu May 13 15:35:44 EDT 2004 

Michel>   7. The last instruction must be RETURN_VALUE?

Nope. Relatively simple analysis of the basic blocks in the bytecode can determine if the trailing push none/return value pair is dead code and remove it if it is.

Michel>   2. The operand of a LOAD_CONST instruction must be an valid
Michel>      index into the co_consts.

Michel>   3. Can a similar bounds check be made at verfication time for
Michel>      LOAD_FAST?

Should be possible, yes.

Michel>   4. Can index into co_names, co_varnames, co_freevars,
Michel>      co_cellvars be verfied?

Also yes. These are all fixed-length arrays (tuples actually) whose lengths are determined at compile-time.

Skip

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