`A4-7-1`: integer data loss false positive erasing from container

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp
Domain
tooling

Research direction

Start at the A4-7-1 rule entry point and reproduce the reported container example, focusing on the emptiness check before decrementing num_items_. Done means this guarded decrement is no longer reported as integer data loss while genuine wrap-around cases remain covered.

Written by the indexing model from the issue text.

Description

Difficulty-High false positive/false negative Impact-Medium Standard-AUTOSAR
Affected rules
  • A4-7-1
Description

Decrement cannot lead to wrap-around since the container is checked for emptiness.

Example
class container
{
    bool empty()
    {
        return num_items_ == 0;
    }

    void erase()
    {
        if (empty())
            return;

        num_items_--;
    }

    std::size_t num_items_ = 0;
};
Dominant language
CodeQL
Stars
227
Forks
82
Avg merge
6d 7h
Merged PRs (30d)
9

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