Commit ecb9ddf2672fa1f067c240d914a5baf3a4d2d8a4 | zig

author	Brandon Black <bblack@wikimedia.org> 2026-01-28 16:54:04-06:00
committer	Andrew Kelley <andrew@ziglang.org> 2026-01-30 06:19:31+01:00
log	ecb9ddf2672fa1f067c240d914a5baf3a4d2d8a4
tree	b819f184ff9070176c232acd5afce33d473b0678
parent	9b415761dd66904aef363e387b4501f3ddd0bf76

Threaded.sleepPosix: fix libc error handling

Confusingly, the POSIX spec for clock_nanosleep() says it returns
*positive* error values directly and does not touch `errno`. Not
detecting EINTR properly here was breaking the cancellation of
threads blocked in this call when linking libc.

1 files changed, 4 insertions(+), 2 deletions(-)

lib
- std
  - Io
    Threaded.zig

lib/std/Io/Threaded.zig+4-2

 @@ -10083,10 +10083,12 @@ fn sleepPosix(timeout: Io.Timeout) Io.SleepError!void {
     var timespec: posix.timespec = timestampToPosix(deadline_nanoseconds);
     const syscall: Syscall = try .start();
     while (true) {
-        switch (posix.errno(posix.system.clock_nanosleep(clock_id, .{ .ABSTIME = switch (timeout) {
+        const rc = posix.system.clock_nanosleep(clock_id, .{ .ABSTIME = switch (timeout) {
             .none, .duration => false,
             .deadline => true,
-        } }, &timespec, &timespec))) {
+        } }, &timespec, &timespec);
+        // POSIX-standard libc clock_nanosleep() returns *positive* errno values directly
+        switch (if (builtin.link_libc) @as(posix.E, @enumFromInt(rc)) else posix.errno(rc)) {
             .SUCCESS => {
                 syscall.finish();
                 return;