You might be interested in the scpptool feature to help convert C code to a subset of C that will also compile as C++ (under clang++ at least) [1]. While many of the necessary modifications are fairly trivial, some of them aren't completely so. For example, C++ does not allow `goto`s that would skip over the declaration/initialization of a variable that would be accessible after the jump. So getting the C code to work as C++ can involve some (automatic) code restructuring.

Another annoying detail is that C++ doesn't seem to like forward references of `enum`s. That is, while

    struct A* a_ptr;

is fine in both C and C++ even before `struct A` has been defined, apparently

    enum A* a_ptr;

is not cool in C++ until after `enum A` has been defined.

One arguable benefit of keeping your C code compatible with (or at least convertible to) C++, is that you can theoretically use scpptool's auto-translation feature as build step to produce memory-safe executables from C code via transpilation to a memory-safe subset of C++.

[1] https://github.com/duneroadrunner/SaferCPlusPlus-AutoTransla...