From 92407bfcd7b65f153b7523d97ac5f69193561d27 Mon Sep 17 00:00:00 2001
From: Joran Dirk Greef <joran@ronomon.com>
Date: Sat, 19 Sep 2020 18:29:50 +0200
Subject: [PATCH] Upgrade check_errno() to an exhaustive switch (safer)

---
 lib/std/os/linux/io_uring.zig | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/std/os/linux/io_uring.zig b/lib/std/os/linux/io_uring.zig
index 82c7dd7cc4..2c17614b04 100644
--- a/lib/std/os/linux/io_uring.zig
+++ b/lib/std/os/linux/io_uring.zig
@@ -608,10 +608,10 @@ pub const CompletionQueue = struct {
 };
 
 inline fn check_errno(res: usize) !void {
-    const errno = linux.getErrno(res);
-    if (errno != 0) {
-        if (errno == linux.ENOSYS) return error.UnsupportedKernel;
-        return os.unexpectedErrno(errno);
+    switch (linux.getErrno(res)) {
+        0 => return,
+        linux.ENOSYS => return error.UnsupportedKernel,
+        else => |errno| return os.unexpectedErrno(errno)
     }
 }