Understanding Software Defects

Understanding Software Defects

Describe 13 major categories of Software defects:

• User interface errors – the system provides something that is different from Interface.
• Error handling – the way the errors are recognized and treated may be in error .
• Boundary-related errors – the treatment of values at the edges of their ranges may be incorrect .
• Calculation errors – arithmetic and logic calculations may be incorrect .
• Initial and later states – the function fails the first time it is used but not later, or Vice-versa .
• Control flow errors – the choice of what is done next is not appropriate for the current state .
• Errors in handling or interpreting data – passing and converting data between systems (and even separate components of the system) may introduce errors.
• Race conditions – when two events could be processed, one is always accepted prior to the other and things work fine, however eventually the other event may be processed first and unexpected or incorrect results are produced.
• Load conditions – as the system is pushed to maximum limits problems start to occur, e.g. arrays overflow, disks full .
• Hardware – interfacing with devices may not operate correctly under certain conditions, e.g. device unavailable .
• Source and version control - out-of-date programs may be used where correct revisions are available.
• Documentation – the user does not observe operation described in manuals .
• Testing errors – the tester makes mistakes during testing and thinks the system is behaving incorrectly.