use RtlCaptureStackBackTrace on windows

4 files changed, 9 insertions, 2 deletions

diff --git a/std/os/file.zig b/std/os/file.zig
index d63cb1deaa..e90275ec7f 100644
--- a/std/os/file.zig
+++ b/std/os/file.zig
@@ -271,6 +271,7 @@ pub const File = struct {
                     const err = windows.GetLastError();
                     return switch (err) {
                         windows.ERROR.INVALID_PARAMETER => unreachable,
+                        windows.ERROR.INVALID_HANDLE => unreachable,
                         else => os.unexpectedErrorWindows(err),
                     };
                 }
diff --git a/std/os/index.zig b/std/os/index.zig
index 74f94dce5a..03337b63bc 100644
--- a/std/os/index.zig
+++ b/std/os/index.zig
@@ -661,6 +661,7 @@ pub fn getBaseAddress() usize {
             return phdr - @sizeOf(ElfHeader);
         },
         builtin.Os.macosx => return @ptrToInt(&std.c._mh_execute_header),
+        builtin.Os.windows => return @ptrToInt(windows.GetModuleHandleW(null)),
         else => @compileError("Unsupported OS"),
     }
 }
@@ -2069,7 +2070,7 @@ fn testWindowsCmdLine(input_cmd_line: [*]const u8, expected_args: []const []cons
 }
 
 // TODO make this a build variable that you can set
-const unexpected_error_tracing = false;
+const unexpected_error_tracing = true;
 const UnexpectedError = error{
     /// The Operating System returned an undocumented error code.
     Unexpected,
@@ -2088,8 +2089,9 @@ pub fn unexpectedErrorPosix(errno: usize) UnexpectedError {
 /// Call this when you made a windows DLL call or something that does SetLastError
 /// and you get an unexpected error.
 pub fn unexpectedErrorWindows(err: windows.DWORD) UnexpectedError {
-    if (true) {
+    if (unexpected_error_tracing) {
         debug.warn("unexpected GetLastError(): {}\n", err);
+        @breakpoint();
         debug.dumpCurrentStackTrace(null);
     }
     return error.Unexpected;
diff --git a/std/os/windows/index.zig b/std/os/windows/index.zig
index 5c68176c5a..ca6299dc5e 100644
--- a/std/os/windows/index.zig
+++ b/std/os/windows/index.zig
@@ -3,6 +3,7 @@ const assert = std.debug.assert;
 
 pub use @import("advapi32.zig");
 pub use @import("kernel32.zig");
+pub use @import("ntdll.zig");
 pub use @import("ole32.zig");
 pub use @import("shell32.zig");
 pub use @import("shlwapi.zig");
diff --git a/std/os/windows/ntdll.zig b/std/os/windows/ntdll.zig
new file mode 100644
index 0000000000..acb78a59f4
--- /dev/null
+++ b/std/os/windows/ntdll.zig
@@ -0,0 +1,3 @@
+use @import("index.zig");
+
+pub extern "NtDll" stdcallcc fn RtlCaptureStackBackTrace(FramesToSkip: DWORD, FramesToCapture: DWORD, BackTrace: **c_void, BackTraceHash: ?*DWORD) WORD;