| Message ID | 20220726121502.1958288-1-dylany@fb.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | multishot recvmsg docs and example | expand |
On Tue, 26 Jul 2022 05:14:57 -0700, Dylan Yudaken wrote: > Some multishot recvmsg patches for liburing: > > Patches 1-3 cleanup the API a little while we're doing this. > Patch 4 adds docs for the new API > Patch 5 adds an example UDP echo server that uses the API > > > [...] Applied, thanks! [1/5] more consistent multishot recvmsg API parameter names commit: c025f206a8d7337109f148a738bf5df75aeed494 [2/5] order like functions together in liburing.h commit: b569b365c3c7d4ac78e8c2f482d5a227a980977f [3/5] change io_uring_recvmsg_payload_length return type commit: 464ed8e15b3dbec2b44e087c4620dcffdc28a753 [4/5] add documentation for multishot recvmsg commit: 06f979baaae2c5a17f6b4233cb1f1d6720378149 [5/5] add an example for a UDP server commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 Best regards,
On 7/26/22 11:23 PM, Jens Axboe wrote: > [5/5] add an example for a UDP server > commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 This one breaks clang-13 build, I'll send a patch.
On 7/26/22 10:32 AM, Ammar Faizi wrote: > > > On 7/26/22 11:23 PM, Jens Axboe wrote: >> [5/5] add an example for a UDP server >> commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 > > This one breaks clang-13 build, I'll send a patch. Hmm, built fine with clang-13/14 here?
On 7/26/22 11:40 PM, Jens Axboe wrote: > On 7/26/22 10:32 AM, Ammar Faizi wrote: >> On 7/26/22 11:23 PM, Jens Axboe wrote: >>> [5/5] add an example for a UDP server >>> commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 >> >> This one breaks clang-13 build, I'll send a patch. > > Hmm, built fine with clang-13/14 here? Not sure what is going on, but clang-13 on my machine is not happy: io_uring-udp.c:134:18: error: incompatible pointer types passing \ 'struct sockaddr_in6 *' to parameter of type 'const struct sockaddr *' \ [-Werror,-Wincompatible-pointer-types io_uring-udp.c:142:18: error: incompatible pointer types passing \ 'struct sockaddr_in *' to parameter of type 'const struct sockaddr *' \ [-Werror,-Wincompatible-pointer-types] Changing the compiler to GCC builds just fine. I have fixed something like this more than once. Strange indeed.
On 7/26/22 10:48 AM, Ammar Faizi wrote: > On 7/26/22 11:40 PM, Jens Axboe wrote: >> On 7/26/22 10:32 AM, Ammar Faizi wrote: >>> On 7/26/22 11:23 PM, Jens Axboe wrote: >>>> [5/5] add an example for a UDP server >>>> commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 >>> >>> This one breaks clang-13 build, I'll send a patch. >> >> Hmm, built fine with clang-13/14 here? > > Not sure what is going on, but clang-13 on my machine is not happy: > > io_uring-udp.c:134:18: error: incompatible pointer types passing \ > 'struct sockaddr_in6 *' to parameter of type 'const struct sockaddr *' \ > [-Werror,-Wincompatible-pointer-types > > io_uring-udp.c:142:18: error: incompatible pointer types passing \ > 'struct sockaddr_in *' to parameter of type 'const struct sockaddr *' \ > [-Werror,-Wincompatible-pointer-types] > > Changing the compiler to GCC builds just fine. I have fixed something like > this more than once. Strange indeed. Regardless, the patch is sane!
On Tue, 2022-07-26 at 10:49 -0600, Jens Axboe wrote: > > On 7/26/22 10:48 AM, Ammar Faizi wrote: > > On 7/26/22 11:40 PM, Jens Axboe wrote: > > > On 7/26/22 10:32 AM, Ammar Faizi wrote: > > > > On 7/26/22 11:23 PM, Jens Axboe wrote: > > > > > [5/5] add an example for a UDP server > > > > > commit: 61d472b51e761e61cbf46caea40aaf40d8ed1484 > > > > > > > > This one breaks clang-13 build, I'll send a patch. > > > > > > Hmm, built fine with clang-13/14 here? > > > > Not sure what is going on, but clang-13 on my machine is not happy: > > > > io_uring-udp.c:134:18: error: incompatible pointer types > > passing \ > > 'struct sockaddr_in6 *' to parameter of type 'const struct > > sockaddr *' \ > > [-Werror,-Wincompatible-pointer-types > > > > io_uring-udp.c:142:18: error: incompatible pointer types > > passing \ > > 'struct sockaddr_in *' to parameter of type 'const struct > > sockaddr *' \ > > [-Werror,-Wincompatible-pointer-types] > > > > Changing the compiler to GCC builds just fine. I have fixed > > something like > > this more than once. Strange indeed. Interestingly it did not show up on the Github CI either. What flags are you setting for this? Maybe the CI can be expanded to include those flags. As you say its not the first time you've fixed this, or that I've done this. Dylan
On 7/27/22 2:57 PM, Dylan Yudaken wrote: > Interestingly it did not show up on the Github CI either. What flags > are you setting for this? Maybe the CI can be expanded to include those > flags. > As you say its not the first time you've fixed this, or that I've done > this. I use the same flag with the GitHub CI. Just a small experiment here... I compile this with default compilation flags: #include <arpa/inet.h> #include <sys/socket.h> #include <sys/types.h> int main(void) { struct sockaddr_in addr = { }; return bind(0, &addr, sizeof(addr)); } =============================================================================== ammarfaizi2@integral2:/tmp$ gcc test.c -o test test.c: In function ‘main’: test.c:9:24: warning: passing argument 2 of ‘bind’ from incompatible pointer type [-Wincompatible-pointer-types] 9 | return bind(0, &addr, sizeof(addr)); | ^~~~~ | | | struct sockaddr_in * In file included from /usr/include/netinet/in.h:23, from /usr/include/arpa/inet.h:22, from test.c:2: /usr/include/x86_64-linux-gnu/sys/socket.h:112:49: note: expected ‘const struct sockaddr *’ but argument is of type ‘struct sockaddr_in *’ 112 | extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len) | =============================================================================== ammarfaizi2@integral2:/tmp$ clang test.c -o test test.c:9:17: warning: incompatible pointer types passing 'struct sockaddr_in *' to parameter of type 'const struct sockaddr *' [-Wincompatible-pointer-types] return bind(0, &addr, sizeof(addr)); ^~~~~ /usr/include/x86_64-linux-gnu/sys/socket.h:112:49: note: passing argument to parameter '__addr' here extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len) ^ 1 warning generated. =============================================================================== Interestingly GCC also complains here, but it doesn't complain when compiling your code. Your code only breaks my clang-13. What is the magic behind this? We never disable -Wincompatible-pointer-types in liburing either. It's enabled by default.
On 7/27/22 4:59 PM, Ammar Faizi wrote: > Interestingly GCC also complains here, but it doesn't complain when > compiling your code. Your code only breaks my clang-13. > > What is the magic behind this? OK, I figured it out. This work: gcc -D_GNU_SOURCE test.c -o test; These 3 break: clang -D_GNU_SOURCE test.c -o test; clang test.c -o test; gcc test.c -o test; So -D_GNU_SOURCE is the culprit. It seems to be unavoidable as the warn seems to be compiler specific or something. Maybe that _GNU_SOURCE patches the definition of bind().
On 7/27/22 5:11 PM, Ammar Faizi wrote: > So -D_GNU_SOURCE is the culprit. It seems to be unavoidable as > the warn seems to be compiler specific or something. Maybe that > _GNU_SOURCE patches the definition of bind(). I did: gcc -E -D_GNU_SOURCE test.c -o xtest.c and examined the xtest.c output. So basically when we use _GNU_SOURCE, sometimes the declaration of bind() is like this: extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len) __attribute__ ((__nothrow__ , __leaf__)); With __CONST_SOCKADDR_ARG being a union: typedef union { const struct sockaddr *__restrict __sockaddr__; const struct sockaddr_at *__restrict __sockaddr_at__; const struct sockaddr_ax25 *__restrict __sockaddr_ax25__; const struct sockaddr_dl *__restrict __sockaddr_dl__; const struct sockaddr_eon *__restrict __sockaddr_eon__; const struct sockaddr_in *__restrict __sockaddr_in__; const struct sockaddr_in6 *__restrict __sockaddr_in6__; const struct sockaddr_inarp *__restrict __sockaddr_inarp__; const struct sockaddr_ipx *__restrict __sockaddr_ipx__; const struct sockaddr_iso *__restrict __sockaddr_iso__; const struct sockaddr_ns *__restrict __sockaddr_ns__; const struct sockaddr_un *__restrict __sockaddr_un__; const struct sockaddr_x25 *__restrict __sockaddr_x25__; } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__)); But not all header file included by the compiler has this union stuff. When it doesn't, it will throw a warning like that.