Fix MISRA 10.8 violation in okj_measure_container#68
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Replace pointer-subtraction cast `(uint16_t)(p - start)` with an incrementally maintained uint16_t counter, avoiding a cast from a composite expression (ptrdiff_t) to a different essential type category. https://claude.ai/code/session_01L2o12dqmUBCrvj7Lo2WExs
Add `len == p - start` invariant to both the outer and inner loops in okj_measure_container so the WP plugin can prove the postcondition `\result <= end - start` without timeout. https://claude.ai/code/session_01L2o12dqmUBCrvj7Lo2WExs
Add `assert len == p - start` after each paired p++/len++ site so the prover can maintain the loop invariant across all control flow paths without timing out. https://claude.ai/code/session_01L2o12dqmUBCrvj7Lo2WExs
Replace the len-counter approach (which introduced Frama-C timeouts) with a simpler decomposition: store the pointer difference in a local `long` variable before casting to uint16_t. This makes the cast operand a simple lvalue rather than a composite expression, satisfying MISRA 10.8 without changing any loop logic or Frama-C annotations. https://claude.ai/code/session_01L2o12dqmUBCrvj7Lo2WExs
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Summary\n\n- Replace
(uint16_t)(p - start)pointer-subtraction cast with an incrementally maintaineduint16_t lencounter\n- This avoids casting a composite expression (ptrdiff_t) to a different essential type category, which violates MISRA Rule 10.8\n- All existing tests pass\n\n## Test plan\n\n- [x] Full test suite passes (make clean && make)\n- [ ] Verify with MISRA static analysis tooling that Rule 10.8 is no longer flagged forokj_measure_container\n\nhttps://claude.ai/code/session_01L2o12dqmUBCrvj7Lo2WExs