iwyu (Include What You Use) has just been accepted in Debian.

This tool, based on LLVM/Clang, checks the headers of a C/C++ file. It will detect which include directives are useless, what could be improve and add comments to explain why #include are there.

Let's take this C file:

#include <stdio.h>
#include <malloc.h>
#include <limits.h>

int foo(void) {
fprintf(stderr, "an error\n");
return INT_MAX;
}


$ iwyu foo.c

will return:

foo.c should remove these lines:
- #include <malloc.h> // lines 2-2

The full include-list for foo.c:
#include <limits.h> // for INT_MAX
#include <stdio.h> // for fprintf, stderr
---


Package on Debian