diff --git a/lib/std/Io/File.zig b/lib/std/Io/File.zig
index d0f487b911..e537755a33 100644
--- a/lib/std/Io/File.zig
+++ b/lib/std/Io/File.zig
@@ -10,20 +10,8 @@ const assert = std.debug.assert;
 const Dir = std.Io.Dir;
 
 handle: Handle,
-flags: Flags = .{},
 
 pub const Handle = std.posix.fd_t;
-pub const Flags = switch (native_os) {
-    .windows => packed struct(u1) {
-        /// * true: opened with MODE.IO.ASYNCHRONOUS
-        /// * false: opened with SYNCHRONOUS_ALERT or SYNCHRONOUS_NONALERT, or
-        ///   not a file.
-        /// This is default-initialized to false as a workaround for
-        /// https://codeberg.org/ziglang/zig/issues/30842
-        nonblocking: bool = false,
-    },
-    else => packed struct(u0) {},
-};
 
 pub const Reader = @import("File/Reader.zig");
 pub const Writer = @import("File/Writer.zig");
@@ -89,7 +77,6 @@ pub fn stdout() File {
     return switch (native_os) {
         .windows => .{
             .handle = std.os.windows.peb().ProcessParameters.hStdOutput,
-            .flags = .{ .nonblocking = false },
         },
         else => .{
             .handle = std.posix.STDOUT_FILENO,
@@ -101,7 +88,6 @@ pub fn stderr() File {
     return switch (native_os) {
         .windows => .{
             .handle = std.os.windows.peb().ProcessParameters.hStdError,
-            .flags = .{ .nonblocking = false },
         },
         else => .{
             .handle = std.posix.STDERR_FILENO,
@@ -113,7 +99,6 @@ pub fn stdin() File {
     return switch (native_os) {
         .windows => .{
             .handle = std.os.windows.peb().ProcessParameters.hStdInput,
-            .flags = .{ .nonblocking = false },
         },
         else => .{
             .handle = std.posix.STDIN_FILENO,
diff --git a/lib/std/Io/Threaded.zig b/lib/std/Io/Threaded.zig
index cdbb0fd182..1a2ca61c00 100644
--- a/lib/std/Io/Threaded.zig
+++ b/lib/std/Io/Threaded.zig
@@ -2764,12 +2764,7 @@ fn dirCreateDirPathOpenWasi(
 
 fn dirStat(userdata: ?*anyopaque, dir: Dir) Dir.StatError!Dir.Stat {
     const t: *Threaded = @ptrCast(@alignCast(userdata));
-    const file: File = if (is_windows) .{
-        .handle = dir.handle,
-        .flags = .{ .nonblocking = false },
-    } else .{
-        .handle = dir.handle,
-    };
+    const file: File = .{ .handle = dir.handle };
     return fileStat(t, file);
 }
 
@@ -3692,10 +3687,7 @@ fn dirCreateFileWindows(
     errdefer windows.CloseHandle(handle);
 
     const exclusive = switch (flags.lock) {
-        .none => return .{
-            .handle = handle,
-            .flags = .{ .nonblocking = false },
-        },
+        .none => return .{ .handle = handle },
         .shared => false,
         .exclusive => true,
     };
@@ -3715,10 +3707,7 @@ fn dirCreateFileWindows(
     )) {
         .SUCCESS => {
             syscall.finish();
-            return .{
-                .handle = handle,
-                .flags = .{ .nonblocking = false },
-            };
+            return .{ .handle = handle };
         },
         .INSUFFICIENT_RESOURCES => return syscall.fail(error.SystemResources),
         .LOCK_NOT_GRANTED => return syscall.fail(error.WouldBlock),
@@ -4289,10 +4278,7 @@ pub fn dirOpenFileWtf16(
     errdefer w.CloseHandle(handle);
 
     const exclusive = switch (flags.lock) {
-        .none => return .{
-            .handle = handle,
-            .flags = .{ .nonblocking = false },
-        },
+        .none => return .{ .handle = handle },
         .shared => false,
         .exclusive => true,
     };
@@ -4315,10 +4301,7 @@ pub fn dirOpenFileWtf16(
         .ACCESS_VIOLATION => |err| return syscall.ntstatusBug(err), // bad io_status_block pointer
         else => |status| return syscall.unexpectedNtstatus(status),
     };
-    return .{
-        .handle = handle,
-        .flags = .{ .nonblocking = false },
-    };
+    return .{ .handle = handle };
 }
 
 fn dirOpenFileWasi(
@@ -8414,7 +8397,7 @@ fn fileReadStreamingWindows(file: File, data: []const []u8) File.Reader.Error!us
                     try syscall.checkCancel();
                     continue;
                 },
-                .INVALID_PARAMETER => |err| return syscall.ntstatusBug(err), // wrong value for flags.nonblocking
+                .INVALID_PARAMETER => |err| return syscall.ntstatusBug(err), // streaming read of async mode file
                 else => |status| return syscall.unexpectedNtstatus(status),
             }
         }
@@ -14602,9 +14585,9 @@ fn processSpawnWindows(userdata: ?*anyopaque, options: process.SpawnOptions) pro
     return .{
         .id = piProcInfo.hProcess,
         .thread_handle = piProcInfo.hThread,
-        .stdin = if (g_hChildStd_IN_Wr) |h| .{ .handle = h, .flags = .{ .nonblocking = true } } else null,
-        .stdout = if (g_hChildStd_OUT_Rd) |h| .{ .handle = h, .flags = .{ .nonblocking = true } } else null,
-        .stderr = if (g_hChildStd_ERR_Rd) |h| .{ .handle = h, .flags = .{ .nonblocking = true } } else null,
+        .stdin = if (g_hChildStd_IN_Wr) |h| .{ .handle = h } else null,
+        .stdout = if (g_hChildStd_OUT_Rd) |h| .{ .handle = h } else null,
+        .stderr = if (g_hChildStd_ERR_Rd) |h| .{ .handle = h } else null,
         .request_resource_usage_statistics = options.request_resource_usage_statistics,
     };
 }
@@ -15738,7 +15721,6 @@ fn progressParentFile(userdata: ?*anyopaque) std.Progress.ParentFileError!File {
             .pointer => @ptrFromInt(int),
             else => return error.UnsupportedOperation,
         },
-        .flags = if (is_windows) .{ .nonblocking = true } else .{},
     };
 }
 
diff --git a/lib/std/Progress.zig b/lib/std/Progress.zig
index 5da6111079..5ccc46778b 100644
--- a/lib/std/Progress.zig
+++ b/lib/std/Progress.zig
@@ -979,7 +979,6 @@ fn serializeIpc(start_serialized_len: usize, serialized_buffer: *Serialized.Buff
         if (main_parent == .unused) continue;
         const file: Io.File = .{
             .handle = main_storage.getIpcFd() orelse continue,
-            .flags = if (is_windows) .{ .nonblocking = true } else .{},
         };
         const opt_saved_metadata = findOld(file.handle, old_ipc_metadata_fds, old_ipc_metadata);
         var bytes_read: usize = 0;