KubaO / KubaO/stackoverflown

Incorrect comparison function - violates strict weak ordering

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Dominant language
C++
Stars
65
Forks
25
PR merge metrics
No merged PRs in 30d

Description

https://github.com/KubaO/stackoverflown/blob/b3d59cfa491140759991f8a50392c785c9c50127/questions/qmap-qcolor-32512125/main.cpp#L4-L8

This comparison function violates the requirement for Strict Weak Ordering and will cause undefined behaviour/corruption inside the map.

Consider colours A(255, 0, 0) and B(0, 255, 0). Both A < B and B < A will return true.

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Research direction

Open the linked questions/qmap-qcolor-32512125/main.cpp lines 4-8 and inspect the colour comparison function. Check it with the A and B values given in the issue; done means the comparison no longer reports both A < B and B < A, preserving valid map ordering.

Written by the indexing model from the issue text.

Assessment

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

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