================ @@ -0,0 +1,50 @@ +.. title:: clang-tidy - bugprone-virtual-arithmetic + +bugprone-virtual-arithmetic +=========================== + +Warn if pointer arithmetic is performed on a class that declares a +virtual function. + +Pointer arithmetic on polymorphic objects where the pointer's static type is +different from its dynamic type is undefined behavior. +Finding pointers where the static type contains a virtual member function is a +good heuristic, as the pointer is likely to point to a different, derived class. + +This check corresponds to the SEI Cert rule `CTR56-CPP: Do not use pointer arithmetic on polymorphic objects <https://wiki.sei.cmu.edu/confluence/display/cplusplus/CTR56-CPP.+Do+not+use+pointer+arithmetic+on+polymorphic+objects>`_. + +Example: + +.. code-block:: c++ + + struct Base { + virtual void ~Base(); + }; + + struct Derived : public Base {}; + + void foo() { + Base *b = new Derived[10]; + + b += 1; + // warning: pointer arithmetic on class that declares a virtual function, undefined behavior if the pointee is a different class ---------------- 5chmidti wrote:
Please reflow this comment to fit into 80 columns. https://github.com/llvm/llvm-project/pull/91951 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
