The document discusses different types of bugs that can occur in code including memory access bugs, threading bugs, and undefined behavior bugs. Memory access bugs include buffer overflows, erroneous type casts, use-after-free errors, and memory leaks. Threading bugs involve issues with mutexes, deadlocks, data races, and race conditions during object construction and destruction. Undefined behavior bugs result from violations of initialization order, the one definition rule, lack of sequence points, and integer overflows.

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Artem Melnytskyi
A Little About the
Bugs in the Code

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Coding
Coffee
Code review
About me
Code review
Coding
Coffee

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It’s about
• Bug classification
• Memory access bugs
• Threading bugs
• Undefined behavior bug

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Before the beginning…
• Nothing here claims to be the truth in the last instance.
• Yes, I know that on another compiler, and another platform (on which
you were lucky enough to work) this may not be so.

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Memory
access bugs
Buffer
overflow
Erroneous
type cast
Use-after-
free
Use-after-
return
Use-after-
scope
[De]allocation
bugs
Memory
leaks
Use of
uninitialized
memory
Threadin
g bugs
Mutex
Deadlock
Data
Races
Race on a
bitfield
Race
During
Destructio
n VPTR:
constructio
n order
Race on
VPTR
Race on
VPTR (cont)
Atomicity
violation
Atomicity violation
(cont)
Other
Undefined
Behavior
Init Order
Fiasco
ODR (one
definition
rule)
Violation
Lack of
Sequence
Point
Integer
Overflow
Bug classification

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bug in
GCC
Memory access bugs

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bug in
GCC
Memory access bugs

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bug in
GCC
Memory access bugs

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bug in
GCC
Memory access bugs

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Алло RAIIчка, ты сейчас
упадешь!
Memory access bugs

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Memory access bugs

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Memory access bugs

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https://www.viva64.com/en/a/0079/
100 Bugs in Open Source C/C++ projects

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Memory access bugs

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Threading bugs

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Threading bugs

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Threading bugs

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Continue...

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VPTR RACE

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Other Undefined Behavior

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THANK YOU!