From d6402955d962b1563378b44a82a9644cee344ff3 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Fri, 13 Mar 2026 15:29:25 -0700
Subject: [PATCH] kernel32: another one bytes the dust

---
 lib/std/os/windows.zig          | 16 ++--------------
 lib/std/os/windows/kernel32.zig | 19 -------------------
 2 files changed, 2 insertions(+), 33 deletions(-)

diff --git a/lib/std/os/windows.zig b/lib/std/os/windows.zig
index f38b340703fcf4447e324f8ad6213acae39979cf..1dabd71422d8e715ec567011752df2acf452de0c 100644
--- a/lib/std/os/windows.zig
+++ b/lib/std/os/windows.zig
@@ -3211,21 +3211,9 @@ inline fn MAKELANGID(p: c_ushort, s: c_ushort) LANGID {
 /// Call this when you made a windows DLL call or something that does SetLastError
 /// and you get an unexpected error.
 pub fn unexpectedError(err: Win32Error) UnexpectedError {
+    @branchHint(.cold);
     if (std.posix.unexpected_error_tracing) {
-        // 614 is the length of the longest windows error description
-        var buf_wstr: [614:0]WCHAR = undefined;
-        const len = kernel32.FormatMessageW(
-            FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
-            null,
-            err,
-            MAKELANGID(LANG.NEUTRAL, SUBLANG.DEFAULT),
-            &buf_wstr,
-            buf_wstr.len,
-            null,
-        );
-        std.debug.print("error.Unexpected: GetLastError({d}): {f}\n", .{
-            err, std.unicode.fmtUtf16Le(buf_wstr[0..len]),
-        });
+        std.debug.print("error.Unexpected: GetLastError({d}): {t}\n", .{ err, err });
         std.debug.dumpCurrentStackTrace(.{ .first_address = @returnAddress() });
     }
     return error.Unexpected;
diff --git a/lib/std/os/windows/kernel32.zig b/lib/std/os/windows/kernel32.zig
index 894ef96a7ef0a2f4efde753c276c09bd0887bbc1..649d09cc6256cccc49d9a18d2834e16e5450e36c 100644
--- a/lib/std/os/windows/kernel32.zig
+++ b/lib/std/os/windows/kernel32.zig
@@ -4,7 +4,6 @@ const windows = std.os.windows;
 const BOOL = windows.BOOL;
 const DWORD = windows.DWORD;
 const HANDLE = windows.HANDLE;
-const LPCVOID = windows.LPCVOID;
 const LPCWSTR = windows.LPCWSTR;
 const LPVOID = windows.LPVOID;
 const LPWSTR = windows.LPWSTR;
@@ -13,10 +12,6 @@ const THREAD_START_ROUTINE = windows.THREAD_START_ROUTINE;
 const SECURITY_ATTRIBUTES = windows.SECURITY_ATTRIBUTES;
 const SIZE_T = windows.SIZE_T;
 const STARTUPINFOW = windows.STARTUPINFOW;
-const va_list = windows.va_list;
-const Win32Error = windows.Win32Error;
-
-// Process Management
 
 pub extern "kernel32" fn CreateProcessW(
     lpApplicationName: ?LPCWSTR,
@@ -31,8 +26,6 @@ pub extern "kernel32" fn CreateProcessW(
     lpProcessInformation: *PROCESS.INFORMATION,
 ) callconv(.winapi) BOOL;
 
-// Threading
-
 // TODO: CreateRemoteThread with hProcess=NtCurrentProcess().
 pub extern "kernel32" fn CreateThread(
     lpThreadAttributes: ?*SECURITY_ATTRIBUTES,
@@ -42,15 +35,3 @@ pub extern "kernel32" fn CreateThread(
     dwCreationFlags: DWORD,
     lpThreadId: ?*DWORD,
 ) callconv(.winapi) ?HANDLE;
-
-// Error Management
-
-pub extern "kernel32" fn FormatMessageW(
-    dwFlags: DWORD,
-    lpSource: ?LPCVOID,
-    dwMessageId: Win32Error,
-    dwLanguageId: DWORD,
-    lpBuffer: LPWSTR,
-    nSize: DWORD,
-    Arguments: ?*va_list,
-) callconv(.winapi) DWORD;
-- 
2.54.0