diff options
Diffstat (limited to 'lib/std/start.zig')
| -rw-r--r-- | lib/std/start.zig | 116 |
1 files changed, 89 insertions, 27 deletions
diff --git a/lib/std/start.zig b/lib/std/start.zig index 0fb96c768f..5454cc58c6 100644 --- a/lib/std/start.zig +++ b/lib/std/start.zig @@ -7,7 +7,7 @@ const root = @import("root"); const std = @import("std.zig"); -const builtin = std.builtin; +const builtin = @import("builtin"); const assert = std.debug.assert; const uefi = std.os.uefi; const tlcsprng = @import("crypto/tlcsprng.zig"); @@ -17,39 +17,101 @@ var argc_argv_ptr: [*]usize = undefined; const start_sym_name = if (builtin.arch.isMIPS()) "__start" else "_start"; comptime { - if (builtin.output_mode == .Lib and builtin.link_mode == .Dynamic) { - if (builtin.os.tag == .windows and !@hasDecl(root, "_DllMainCRTStartup")) { - @export(_DllMainCRTStartup, .{ .name = "_DllMainCRTStartup" }); + // The self-hosted compiler is not fully capable of handling all of this start.zig file. + // Until then, we have simplified logic here for self-hosted. TODO remove this once + // self-hosted is capable enough to handle all of the real start.zig logic. + if (builtin.zig_is_stage2) { + if (builtin.output_mode == .Exe) { + if (builtin.link_libc or builtin.object_format == .c) { + if (!@hasDecl(root, "main")) { + @export(main2, "main"); + } + } else { + if (!@hasDecl(root, "_start")) { + @export(_start2, "_start"); + } + } } - } else if (builtin.output_mode == .Exe or @hasDecl(root, "main")) { - if (builtin.link_libc and @hasDecl(root, "main")) { - if (@typeInfo(@TypeOf(root.main)).Fn.calling_convention != .C) { - @export(main, .{ .name = "main", .linkage = .Weak }); + } else { + if (builtin.output_mode == .Lib and builtin.link_mode == .Dynamic) { + if (builtin.os.tag == .windows and !@hasDecl(root, "_DllMainCRTStartup")) { + @export(_DllMainCRTStartup, .{ .name = "_DllMainCRTStartup" }); } - } else if (builtin.os.tag == .windows) { - if (!@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup") and - !@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup")) - { - @export(WinStartup, .{ .name = "wWinMainCRTStartup" }); - } else if (@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup") and - !@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup")) - { - @compileError("WinMain not supported; declare wWinMain or main instead"); - } else if (@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup") and - !@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup")) - { - @export(wWinMainCRTStartup, .{ .name = "wWinMainCRTStartup" }); + } else if (builtin.output_mode == .Exe or @hasDecl(root, "main")) { + if (builtin.link_libc and @hasDecl(root, "main")) { + if (@typeInfo(@TypeOf(root.main)).Fn.calling_convention != .C) { + @export(main, .{ .name = "main", .linkage = .Weak }); + } + } else if (builtin.os.tag == .windows) { + if (!@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup") and + !@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup")) + { + @export(WinStartup, .{ .name = "wWinMainCRTStartup" }); + } else if (@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup") and + !@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup")) + { + @compileError("WinMain not supported; declare wWinMain or main instead"); + } else if (@hasDecl(root, "wWinMain") and !@hasDecl(root, "wWinMainCRTStartup") and + !@hasDecl(root, "WinMain") and !@hasDecl(root, "WinMainCRTStartup")) + { + @export(wWinMainCRTStartup, .{ .name = "wWinMainCRTStartup" }); + } + } else if (builtin.os.tag == .uefi) { + if (!@hasDecl(root, "EfiMain")) @export(EfiMain, .{ .name = "EfiMain" }); + } else if (builtin.arch.isWasm() and builtin.os.tag == .freestanding) { + if (!@hasDecl(root, start_sym_name)) @export(wasm_freestanding_start, .{ .name = start_sym_name }); + } else if (builtin.os.tag != .other and builtin.os.tag != .freestanding) { + if (!@hasDecl(root, start_sym_name)) @export(_start, .{ .name = start_sym_name }); } - } else if (builtin.os.tag == .uefi) { - if (!@hasDecl(root, "EfiMain")) @export(EfiMain, .{ .name = "EfiMain" }); - } else if (builtin.arch.isWasm() and builtin.os.tag == .freestanding) { - if (!@hasDecl(root, start_sym_name)) @export(wasm_freestanding_start, .{ .name = start_sym_name }); - } else if (builtin.os.tag != .other and builtin.os.tag != .freestanding) { - if (!@hasDecl(root, start_sym_name)) @export(_start, .{ .name = start_sym_name }); } } } +// Simplified start code for stage2 until it supports more language features /// + +fn main2() callconv(.C) c_int { + root.main(); + return 0; +} + +fn _start2() callconv(.Naked) noreturn { + root.main(); + exit2(0); +} + +fn exit2(code: u8) noreturn { + switch (builtin.arch) { + .x86_64 => { + asm volatile ("syscall" + : + : [number] "{rax}" (231), + [arg1] "{rdi}" (code) + : "rcx", "r11", "memory" + ); + }, + .arm => { + asm volatile ("svc #0" + : + : [number] "{r7}" (1), + [arg1] "{r0}" (code) + : "memory" + ); + }, + .aarch64 => { + asm volatile ("svc #0" + : + : [number] "{x8}" (93), + [arg1] "{x0}" (code) + : "memory", "cc" + ); + }, + else => @compileError("TODO"), + } + unreachable; +} + +//////////////////////////////////////////////////////////////////////////////// + fn _DllMainCRTStartup( hinstDLL: std.os.windows.HINSTANCE, fdwReason: std.os.windows.DWORD, |