From fe5da36aa3b1dbeb02276c6628640c68a5922191 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Tue, 3 Feb 2026 01:02:48 -0800
Subject: [PATCH] std.Io make Clock.resolution fallible

---
 lib/std/Io.zig          | 9 +++++++--
 lib/std/Io/Threaded.zig | 4 ++--
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/std/Io.zig b/lib/std/Io.zig
index 09da9b533a..92327e0f5d 100644
--- a/lib/std/Io.zig
+++ b/lib/std/Io.zig
@@ -232,7 +232,7 @@ pub const VTable = struct {
     progressParentFile: *const fn (?*anyopaque) std.Progress.ParentFileError!File,
 
     now: *const fn (?*anyopaque, Clock) Timestamp,
-    clockResolution: *const fn (?*anyopaque, Clock) Duration,
+    clockResolution: *const fn (?*anyopaque, Clock) Clock.ResolutionError!Duration,
     sleep: *const fn (?*anyopaque, Timeout) Cancelable!void,
 
     random: *const fn (?*anyopaque, buffer: []u8) void,
@@ -713,9 +713,14 @@ pub const Clock = enum {
         return io.vtable.now(io.userdata, clock);
     }
 
+    pub const ResolutionError = error{
+        ClockUnavailable,
+        Unexpected,
+    };
+
     /// Reveals the granularity of `clock`. May be zero, indicating
     /// unsupported clock.
-    pub fn resolution(clock: Clock, io: Io) Io.Duration {
+    pub fn resolution(clock: Clock, io: Io) ResolutionError!Io.Duration {
         return io.vtable.clockResolution(io.userdata, clock);
     }
 
diff --git a/lib/std/Io/Threaded.zig b/lib/std/Io/Threaded.zig
index 2cd350f58c..6255d96978 100644
--- a/lib/std/Io/Threaded.zig
+++ b/lib/std/Io/Threaded.zig
@@ -10833,7 +10833,7 @@ fn nowInner(clock: Io.Clock) Io.Timestamp {
     };
 }
 
-fn clockResolution(userdata: ?*anyopaque, clock: Io.Clock) Io.Duration {
+fn clockResolution(userdata: ?*anyopaque, clock: Io.Clock) Io.Clock.ResolutionError!Io.Duration {
     const t: *Threaded = @ptrCast(@alignCast(userdata));
     _ = t;
     return switch (native_os) {
@@ -10872,7 +10872,7 @@ fn clockResolution(userdata: ?*anyopaque, clock: Io.Clock) Io.Duration {
     };
 }
 
-fn clockResolutionPosix(clock: Io.Clock) Io.Duration {
+fn clockResolutionPosix(clock: Io.Clock) Io.Clock.ResolutionError!Io.Duration {
     const clock_id: posix.clockid_t = clockToPosix(clock);
     var timespec: posix.timespec = undefined;
     return switch (posix.errno(posix.system.clock_getres(clock_id, &timespec))) {