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1.. title:: clang-tidy - bugprone-undefined-memory-manipulation2 3bugprone-undefined-memory-manipulation4======================================5 6Finds calls of memory manipulation functions ``memset()``, ``memcpy()`` and7``memmove()`` on non-TriviallyCopyable objects resulting in undefined behavior.8 9Using memory manipulation functions on non-TriviallyCopyable objects can lead10to a range of subtle and challenging issues in C++ code. The most immediate11concern is the potential for undefined behavior, where the state of the object12may become corrupted or invalid. This can manifest as crashes, data corruption,13or unexpected behavior at runtime, making it challenging to identify and14diagnose the root cause. Additionally, misuse of memory manipulation functions15can bypass essential object-specific operations, such as constructors and16destructors, leading to resource leaks or improper initialization.17 18For example, when using ``memcpy`` to copy ``std::string``, pointer data is19being copied, and it can result in a double free issue.20 21.. code-block:: c++22 23 #include <cstring>24 #include <string>25 26 int main() {27 std::string source = "Hello";28 std::string destination;29 30 std::memcpy(&destination, &source, sizeof(std::string));31 32 // Undefined behavior may occur here, during std::string destructor call.33 return 0;34 }35