Will Your Code Survive the Attack of the Zombie Pointers?
summary
C and C++ currently make any pointer to an object invalid at the end of that object’s lifetime, which breaks long‑standing concurrent patterns such as Smith and Brown 1973 LIFO and lock‑free push/pop sequences that rely on ABA and pointer reuse. Examples include a push/pop/pop_all sequence that produces a resurrected address and hazard‑pointer readers that observe reclaimed memory. Compilers disagree (GCC 8.1, Intel 19, Clang 6 produced different results at -O2), and proposed fixes range from limiting to allocated storage duration to C11 atomics/inline asm exemptions, annotations, or tool‑level workarounds; practical advice: hide allocators, use inline asm, and add detection tools.
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