zig rc: UTF-16 (LE) encoding is not supported

[kassane]

Zig Version

0.12.0-dev.935+a1e0b9979

Steps to Reproduce and Observed Behavior

cc: @squeek502

repo test: https://github.com/kassane/wolfssl (forked w/ zig build [v0.12.0-dev])

Tried add

lib.addWin32ResourceFile(.{
        .file = .{ .path = "wolfssl.rc" },
    });

Commands: zig build -DTests -DShared -Dtarget=native-windows (my host is Linux)

error: error(compilation): clang preprocessor failed with stderr:
fatal error: UTF-16 (LE) byte order mark detected in '/home/kassane/Documents/wolfssl/wolfssl.rc', but encoding is not supported

---

lib.addWin32ResourceFile(.{
        .file = .{ .path = "wolfssl.rc" },
        .flags = &.{"/c1200"},
    });

/home/kassane/Documents/wolfssl/wolfssl.rc:1:1: error: invalid command line option(s)
error: unsupported code page: utf16 (id=1200)

Expected Behavior

Works, equal to standalone test:

zig/test/standalone/windows_resources/build.zig

Lines 28 to 35 in 7b9165b

	exe.addWin32ResourceFile(.{
	.file = .{ .path = "res/zig.rc" },
	.flags = &.{"/c65001"}, // UTF-8 code page
	});
	exe.rc_includes = switch (rc_includes) {
	.any => .any,
	.gnu => .gnu,
	};

[squeek502]

This is a known limitation due to the clang preprocessor not supporting UTF-16 files (and AFAIK no preprocessor outside of MSVC supports UTF-16 files).

The relevant resinator issue is squeek502/resinator#5

Since you're forking wolfssl, my suggestion would be to convert wolfssl.rc to UTF-8 (and resource.h too if necessary). This could actually be done via build.zig if you don't want to touch the files themselves (generate a converted file and pass the generated file to addWin32ResourceFile). There's no reason beyond Visual Studio generating the .rc file as UTF-16 that it needs to be UTF-16 (there's not even any non-ASCII characters in it).

I've also opened squeek502/resinator#6 but it wouldn't be a viable workaround for this .rc file.