35 lines
1.3 KiB
ReStructuredText
35 lines
1.3 KiB
ReStructuredText
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.. title:: clang-tidy - bugprone-undefined-memory-manipulation
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bugprone-undefined-memory-manipulation
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======================================
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Finds calls of memory manipulation functions ``memset()``, ``memcpy()`` and
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``memmove()`` on non-TriviallyCopyable objects resulting in undefined behavior.
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Using memory manipulation functions on non-TriviallyCopyable objects can lead
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to a range of subtle and challenging issues in C++ code. The most immediate
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concern is the potential for undefined behavior, where the state of the object
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may become corrupted or invalid. This can manifest as crashes, data corruption,
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or unexpected behavior at runtime, making it challenging to identify and
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diagnose the root cause. Additionally, misuse of memory manipulation functions
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can bypass essential object-specific operations, such as constructors and
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destructors, leading to resource leaks or improper initialization.
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For example, when using ``memcpy`` to copy ``std::string``, pointer data is
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being copied, and it can result in a double free issue.
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.. code-block:: c++
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#include <cstring>
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#include <string>
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int main() {
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std::string source = "Hello";
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std::string destination;
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std::memcpy(&destination, &source, sizeof(std::string));
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// Undefined behavior may occur here, during std::string destructor call.
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return 0;
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}
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