setLibCFile is useless for c++

[vkensou]

Zig Version

0.14.0

Steps to Reproduce and Observed Behavior

To build to android, we must set libc file. But seems libc file is useless for c++ headers on 0.14.0. 0.13.0 was ok.

Codes looks like: https://ziggit.dev/t/cant-build-to-android/9158/4

build.zig

const std = @import("std");

pub fn build(b: *std.Build) void {
    const target = b.standardTargetOptions(.{});
    const optimize = b.standardOptimizeOption(.{});

    const lib = b.addLibrary(.{
        .name = "testso",
        .linkage = .dynamic,
        .root_module = b.createModule(.{
            .target = target,
            .optimize = optimize,
        }),
    });

    lib.linkLibC();

    const system_target = getAndroidTriple(lib.rootModuleTarget()) catch |err| @panic(@errorName(err));

    const android_api_version: u32 = 34;

    const libc = createLibC(b, system_target, android_api_version, "E:\\SDKs\\AndroidSDK\\ndk\\27.0.12077973\\toolchains\\llvm\\prebuilt\\windows-x86_64\\sysroot", "27.0.12077973");

    lib.setLibCFile(libc);

    lib.root_module.addCSourceFile(.{ .file = b.path("test.cpp") });

    b.installArtifact(lib);
}

fn getAndroidTriple(target: std.Target) error{InvalidAndroidTarget}![]const u8 {
    if (target.abi != .android) return error.InvalidAndroidTarget;
    return switch (target.cpu.arch) {
        .x86 => "i686-linux-android",
        .x86_64 => "x86_64-linux-android",
        .arm => "arm-linux-androideabi",
        .aarch64 => "aarch64-linux-android",
        .riscv64 => "riscv64-linux-android",
        else => error.InvalidAndroidTarget,
    };
}

fn createLibC(b: *std.Build, system_target: []const u8, android_api_version: u32, ndk_sysroot_path: []const u8, ndk_version: []const u8) std.Build.LazyPath {
    const libc_file_format =
        \\# Generated by zig-android-sdk. DO NOT EDIT.
        \\
        \\# The directory that contains `stdlib.h`.
        \\# On POSIX-like systems, include directories be found with: `cc -E -Wp,-v -xc /dev/null`
        \\include_dir={[include_dir]s}
        \\
        \\# The system-specific include directory. May be the same as `include_dir`.
        \\# On Windows it's the directory that includes `vcruntime.h`.
        \\# On POSIX it's the directory that includes `sys/errno.h`.
        \\sys_include_dir={[sys_include_dir]s}
        \\
        \\# The directory that contains `crt1.o`.
        \\# On POSIX, can be found with `cc -print-file-name=crt1.o`.
        \\# Not needed when targeting MacOS.
        \\crt_dir={[crt_dir]s}
        \\
        \\# The directory that contains `vcruntime.lib`.
        \\# Only needed when targeting MSVC on Windows.
        \\msvc_lib_dir=
        \\
        \\# The directory that contains `kernel32.lib`.
        \\# Only needed when targeting MSVC on Windows.
        \\kernel32_lib_dir=
        \\
        \\gcc_dir=
    ;

    const include_dir = b.fmt("{s}/usr/include", .{ndk_sysroot_path});
    const sys_include_dir = b.fmt("{s}/usr/include/{s}", .{ ndk_sysroot_path, system_target });
    const crt_dir = b.fmt("{s}/usr/lib/{s}/{d}", .{ ndk_sysroot_path, system_target, android_api_version });

    const libc_file_contents = b.fmt(libc_file_format, .{
        .include_dir = include_dir,
        .sys_include_dir = sys_include_dir,
        .crt_dir = crt_dir,
    });

    const filename = b.fmt("android-libc_target-{s}_version-{d}_ndk-{s}.conf", .{ system_target, android_api_version, if (ndk_version.len > 0) ndk_version else "unknown" });

    const write_file = b.addWriteFiles();
    const android_libc_path = write_file.add(filename, libc_file_contents);
    return android_libc_path;
}

test.cpp

#include <string.h>
#include <stdio.h>
#include <iostream>

int func1()
{
    printf("hello world!");
    std::cout << "hello world" << std::endl;
    return 0;
}

Because --libc [file] does not work, so I generate libc file dynamic.

Compiler report like these:

    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\src/filesystem/directory_iterator.cpp:12:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\src/filesystem
/directory_iterator.cpp:12:
#include <filesystem>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/filesystem:540:12: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/filesystem:540:
#  include <__filesystem/directory_entry.h>
           ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__filesystem/directory_entry.h:19:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__fil
esystem/directory_entry.h:19:
#include <__filesystem/filesystem_error.h>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__filesystem/filesystem_error.h:14:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__fi
lesystem/filesystem_error.h:14:
#include <__filesystem/path.h>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__filesystem/path.h:29:12: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__filesystem/pat
h.h:29:
#  include <iomanip> // for quoted
           ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/iomanip:46:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/iomanip:46:
#include <istream>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/istream:164:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/istream:164:
#include <__ostream/basic_ostream.h>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__ostream/basic_ostream.h:24:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__ostream/
basic_ostream.h:24:
#include <ios>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/ios:220:12: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/ios:220:
#  include <__locale>
           ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__locale:14:10: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__locale:14:
#include <__locale_dir/locale_base_api.h>
         ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__locale_dir/locale_base_api.h:17:12: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__loc
ale_dir/locale_base_api.h:17:
#  include <__locale_dir/locale_base_api/android.h>
           ^
    F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\include/__locale_dir/locale_base_api/android.h:22:12: note: in file included from F:\code2\tools\zig\zig-windows-x86_64-0.14.0\lib\libcxx\inclu
de/__locale_dir/locale_base_api/android.h:22:
#  include <__support/xlocale/__posix_l_fallback.h>

The compiler did not even use the libc file I set up.

Expected Behavior

Build success