Re: buildkernel failure in net/toeplitz.c (commit 3b281d1421a78b588c5fc4182009ce62d8823d95)

[Ian FREISLICH]

On 2025-02-24 09:54, Mark Johnston wrote:
On Mon, Feb 24, 2025 at 03:52:14PM +0800, Zhenlei Huang wrote:


On Feb 24, 2025, at 12:42 PM, Ian FREISLICH <ianfreisl...@gmail.com> wrote:

Hi

Building a kernel today failed with:

-Werror /usr/src/sys/net/toeplitz.c
In file included from /usr/src/sys/net/toeplitz.c:29:
In file included from /usr/src/sys/net/rss_config.h:33:
/usr/src/sys/netinet/in.h:692:23: error: call to undeclared function 'htonl'; 
ISO C99 and later do not support implicit function declarations 
[-Werror,-Wimplicit-function-declaration]
  692 |         return (in.s_addr == htonl(INADDR_BROADCAST) ||
      |                              ^
In file included from /usr/src/sys/net/toeplitz.c:32:
In file included from /usr/src/sys/sys/systm.h:98:
/usr/src/sys/sys/param.h:343:13: error: conflicting types for 'htonl'
  343 | __uint32_t       htonl(__uint32_t);
      |                  ^
/usr/src/sys/netinet/in.h:692:23: note: previous implicit declaration is here
  692 |         return (in.s_addr == htonl(INADDR_BROADCAST) ||

I think this is a result of changes to netinet/in.h (3b281d1421a78) which added 
a static inline function using ntohl() which is not defined in kernel use.

Ian



May you please have a try with this patch ?

```
diff --git a/sys/netinet/in.h b/sys/netinet/in.h
index 0925e3aa7669..4dad4e4fed4d 100644
--- a/sys/netinet/in.h
+++ b/sys/netinet/in.h
@@ -689,8 +689,8 @@ void         in_ifdetach(struct ifnet *);
  static inline bool
  in_broadcast(struct in_addr in)
  {
-       return (in.s_addr == htonl(INADDR_BROADCAST) ||
-           in.s_addr == htonl(INADDR_ANY));
+       return (in.s_addr == INADDR_BROADCAST ||
+           in.s_addr == INADDR_ANY);
  }
```

The `htonl` is pointless here, as INADDR_BROADCAST is all 1s, and INADDR_ANY is 
all 0s.

See the review: it's formally unneeded, as you say, but I think the
conversions should be there in case this function is ever augmented
someday.  I think this patch would also work:

diff --git a/sys/netinet/in.h b/sys/netinet/in.h
index fa710af7cd58..e42422341ada 100644
--- a/sys/netinet/in.h
+++ b/sys/netinet/in.h
@@ -689,8 +689,8 @@ void         in_ifdetach(struct ifnet *);
  static inline bool
  in_broadcast(struct in_addr in)
  {
-       return (in.s_addr == htonl(INADDR_BROADCAST) ||
-           in.s_addr == htonl(INADDR_ANY));
+       return (in.s_addr == __htonl(INADDR_BROADCAST) ||
+           in.s_addr == __htonl(INADDR_ANY));
  }
  
  #define	in_hosteq(s, t)	((s).s_addr == (t).s_addr)

I was going to start a bikeshed: I prefer the style of the original 
because it shows that the author understands the importance of byte 
order. Perhaps the root issue is that htonl is define in both 
arpa/inet.h and netinet/in.h with conditional compilation in and out of 
the kernel. The reason existing uses of htonl work in this header file 
is that they're #defines and not functions and so they're not compiled 
unless they're used.

Ian