This rule is part of MISRA C++:2023.
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Rule 21.6.1 - Dynamic memory should not be used
Category: Advisory
Analysis: Undecidable,Single Translation Unit
Amplification
Dynamic memory refers to any object with dynamic storage duration that is managed using operator new (excluding the
non-allocating placement versions), operator delete, the functions calloc, malloc, realloc,
aligned_alloc and free, or any platform-specific memory allocation or deallocation function.
Uses of dynamic memory may occur implicitly (e.g., when throwing exceptions or using C++ Standard Library classes). Therefore, any
instantiation of a C++ Standard Library entity having a template argument that is a specialization of std::allocator is a
violation of this rule, as is any call to a C++ Standard Library function that may use dynamic memory.
Rationale
It is acknowledged that applications may need to use dynamic memory, leading to violations of this rule. Any uses of dynamic memory need
to be justified through supporting documentation that explains how the issues that have been identified in
[[..:section:dynamic-memory-introduction|dynamic-memory-introduction:chapter:Section]] are managed within the project.
Note: a project may reclassify this rule (see MISRA Compliance ) if the risks related to the use of dynamic memory are
considered to be unacceptable.
Example
auto i = std::make_unique< int32_t >( 42 ); // Non-compliant
auto j = std::vector< int32_t > {}; // Non-compliant
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