Hello!
On Mon, Nov 10, 2008 at 11:34:37PM +0300, Igor Sysoev wrote:
On Mon, Nov 10, 2008 at 09:38:39AM -0800, Eric Benson wrote:
Compiling either 0.6.32 or 0.7.20 on a new Ubuntu 8.10 installation with gcc
4.3.2 causes errors due to a new compiler warning (when combined with the use of
-Werror in CFLAGS). There is now a compiler warning when the return value of
write() is ignored. This causes errors in a number of placees in nginx. I have
included a log showing the compiler output as well as a patch file showing the
changes I made to avoid these errors.
Thank you.
However, there is more elegant way to suppress this warning without
stub variables:
(void) write_fd(...)
Could you test the attached patch ?
No, warn_unused_result warning can't be avoided by casting to
void:
$ cat unused.c
int foo() __attribute__((warn_unused_result));
int
foo()
{
return 1;
}
int
main()
{
(void) foo();
return 0;
}
$ gcc unused.c
unused.c: In function 'main':
unused.c:12: warning: ignoring return value of 'foo', declared with attribute
warn_unused_result
More details here:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25509
However I don't think it's a good idea to use stub variables.
Probably something like
if (ngx_write_fd(...) == NGX_FILE_ERROR) {
/* void */
}
would be better.
p.s. Actually I think that it's glibc's bug. But we probably have
to live with it, at least for some time.
11 messages in ru.sysoev.nginxRe: Compilation errors on Ubuntu 8.10...
.log, .diff
