[jcranmer]

So this proposal retains the C++ feature of not allowing you to do anything with the captured context. Semantically, it's as if you created the captured variables as new function-local variables when you initialized the function call, and the wording makes it UB to modify the captured variables via a pointer.

Where the capture context lives in memory and how it is allocated and deallocated is not precisely specified by the specification, but there specification does permit it to be handled via C++-style scoped destruction. That C has no way for you to manually write this code does not preclude implementations from using that logic internally, especially since most C compilers are also C++ compilers and handling C lambdas as identically to C++ lambdas as possible would have some benefits.