| Message ID | 20240922144613.2103760-1-dario.binacchi@amarulasolutions.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Stephen Hemminger |
| Headers | show |
| Series | [iproute2,RESEND,1/2] arpd: use designated initializers for msghdr structure | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Sun, 22 Sep 2024 16:46:12 +0200 Dario Binacchi <dario.binacchi@amarulasolutions.com> wrote: > This patch fixes the following error: > > arpd.c:442:17: error: initialization of 'int' from 'void *' makes integer from pointer without a cast [-Wint-conversion] > 442 | NULL, 0, > > raised by Buildroot autobuilder [1]. > > In the case in question, the analysis of socket.h [2] containing the > msghdr structure shows that it has been modified with the addition of > padding fields, which cause the compilation error. The use of designated > initializers allows the issue to be fixed. > > struct msghdr { > void *msg_name; > socklen_t msg_namelen; > struct iovec *msg_iov; > #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __BIG_ENDIAN > int __pad1; > #endif > int msg_iovlen; > #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __LITTLE_ENDIAN > int __pad1; > #endif > void *msg_control; > #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __BIG_ENDIAN > int __pad2; > #endif > socklen_t msg_controllen; > #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __LITTLE_ENDIAN > int __pad2; > #endif > int msg_flags; > }; That is a really bad idea to put extra padding in there. > > [1] http://autobuild.buildroot.org/results/e4cdfa38ae9578992f1c0ff5c4edae3cc0836e3c/ > [2] iproute2/host/mips64-buildroot-linux-musl/sysroot/usr/include/sys/socket.h > > Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com> > --- > misc/arpd.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/misc/arpd.c b/misc/arpd.c > index e77ef53928a2..b4935c23eebb 100644 > --- a/misc/arpd.c > +++ b/misc/arpd.c > @@ -437,10 +437,10 @@ static void get_kern_msg(void) > struct iovec iov; > char buf[8192]; > struct msghdr msg = { > - (void *)&nladdr, sizeof(nladdr), > - &iov, 1, > - NULL, 0, > - 0 > + .msg_name = &nladdr, .msg_namelen = sizeof(nladdr), When converting, to named initializer, please put one per line like other code does in iproute. > + .msg_iov = &iov, .msg_iovlen = 1, > + .msg_control = (void *)NULL, .msg_controllen = 0, The C standard says that NULL can be used for void *, cast there is unnecessary. > + .msg_flags = 0 > }; > > iov.iov_base = buf;
diff --git a/misc/arpd.c b/misc/arpd.c index e77ef53928a2..b4935c23eebb 100644 --- a/misc/arpd.c +++ b/misc/arpd.c @@ -437,10 +437,10 @@ static void get_kern_msg(void) struct iovec iov; char buf[8192]; struct msghdr msg = { - (void *)&nladdr, sizeof(nladdr), - &iov, 1, - NULL, 0, - 0 + .msg_name = &nladdr, .msg_namelen = sizeof(nladdr), + .msg_iov = &iov, .msg_iovlen = 1, + .msg_control = (void *)NULL, .msg_controllen = 0, + .msg_flags = 0 }; iov.iov_base = buf;
This patch fixes the following error: arpd.c:442:17: error: initialization of 'int' from 'void *' makes integer from pointer without a cast [-Wint-conversion] 442 | NULL, 0, raised by Buildroot autobuilder [1]. In the case in question, the analysis of socket.h [2] containing the msghdr structure shows that it has been modified with the addition of padding fields, which cause the compilation error. The use of designated initializers allows the issue to be fixed. struct msghdr { void *msg_name; socklen_t msg_namelen; struct iovec *msg_iov; #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __BIG_ENDIAN int __pad1; #endif int msg_iovlen; #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __LITTLE_ENDIAN int __pad1; #endif void *msg_control; #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __BIG_ENDIAN int __pad2; #endif socklen_t msg_controllen; #if __LONG_MAX > 0x7fffffff && __BYTE_ORDER == __LITTLE_ENDIAN int __pad2; #endif int msg_flags; }; [1] http://autobuild.buildroot.org/results/e4cdfa38ae9578992f1c0ff5c4edae3cc0836e3c/ [2] iproute2/host/mips64-buildroot-linux-musl/sysroot/usr/include/sys/socket.h Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com> --- misc/arpd.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)