The primary use-case of defer (cleaning up resources) can be done with __attribute__((__cleanup__(<destructor>))). This effectively allows you to do RAII in C,

The primary use-case of defer (cleaning up resources) can be done with __attribute__((__cleanup__(<destructor>))). This effectively allows you to do RAII in C, though it does require some careful thought when copying variables (you need to "move" them a-la Rust). But the really classic way of doing "defer" in C is to do what Linux does: int foo(void) { char *ptr = malloc(13); int error = 0; error = bar(); if (error < 0) goto out_free; // do something else out_free: free(ptr); return error; } Once you get used to it, it feels very natural to write and understand.