zig build system: change target, compilation, and module APIs

Introduce the concept of "target query" and "resolved target". A target
query is what the user specifies, with some things left to default. A
resolved target has the default things discovered and populated.
In the future, std.zig.CrossTarget will be rename to std.Target.Query.
Introduces `std.Build.resolveTargetQuery` to get from one to the other.

The concept of `main_mod_path` is gone, no longer supported. You have to
put the root source file at the module root now.

* remove deprecated API
* update build.zig for the breaking API changes in this branch
* move std.Build.Step.Compile.BuildId to std.zig.BuildId
* add more options to std.Build.ExecutableOptions, std.Build.ObjectOptions,
  std.Build.SharedLibraryOptions, std.Build.StaticLibraryOptions, and
  std.Build.TestOptions.
* remove `std.Build.constructCMacro`. There is no use for this API.
* deprecate `std.Build.Step.Compile.defineCMacro`. Instead,
  `std.Build.Module.addCMacro` is provided.
  - remove `std.Build.Step.Compile.defineCMacroRaw`.
* deprecate `std.Build.Step.Compile.linkFrameworkNeeded`
  - use `std.Build.Module.linkFramework`
* deprecate `std.Build.Step.Compile.linkFrameworkWeak`
  - use `std.Build.Module.linkFramework`
* move more logic into `std.Build.Module`
* allow `target` and `optimize` to be `null` when creating a Module.
  Along with other fields, those unspecified options will be inherited
  from parent `Module` when inserted into an import table.
* the `target` field of `addExecutable` is now required. pass `b.host`
  to get the host target.

3 files changed, 5 insertions, 8 deletions

diff --git a/src/Compilation.zig b/src/Compilation.zig
index 296b300f8d..7831a58840 100644
--- a/src/Compilation.zig
+++ b/src/Compilation.zig
@@ -30,7 +30,6 @@ const fatal = @import("main.zig").fatal;
 const clangMain = @import("main.zig").clangMain;
 const Module = @import("Module.zig");
 const InternPool = @import("InternPool.zig");
-const BuildId = std.Build.CompileStep.BuildId;
 const Cache = std.Build.Cache;
 const c_codegen = @import("codegen/c.zig");
 const libtsan = @import("libtsan.zig");
@@ -910,7 +909,7 @@ pub const InitOptions = struct {
     linker_print_map: bool = false,
     linker_opt_bisect_limit: i32 = -1,
     each_lib_rpath: ?bool = null,
-    build_id: ?BuildId = null,
+    build_id: ?std.zig.BuildId = null,
     disable_c_depfile: bool = false,
     linker_z_nodelete: bool = false,
     linker_z_notext: bool = false,
diff --git a/src/link.zig b/src/link.zig
index 12b9c58d9b..09669f4dbe 100644
--- a/src/link.zig
+++ b/src/link.zig
@@ -10,7 +10,6 @@ const wasi_libc = @import("wasi_libc.zig");
 
 const Air = @import("Air.zig");
 const Allocator = std.mem.Allocator;
-const BuildId = std.Build.CompileStep.BuildId;
 const Cache = std.Build.Cache;
 const Compilation = @import("Compilation.zig");
 const LibCInstallation = @import("libc_installation.zig").LibCInstallation;
@@ -185,7 +184,7 @@ pub const Options = struct {
     error_return_tracing: bool,
     skip_linker_dependencies: bool,
     each_lib_rpath: bool,
-    build_id: BuildId,
+    build_id: std.zig.BuildId,
     disable_lld_caching: bool,
     is_test: bool,
     hash_style: HashStyle,
diff --git a/src/main.zig b/src/main.zig
index 73316c6e65..0e6ce947aa 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -21,7 +21,6 @@ const introspect = @import("introspect.zig");
 const EnvVar = introspect.EnvVar;
 const LibCInstallation = @import("libc_installation.zig").LibCInstallation;
 const wasi_libc = @import("wasi_libc.zig");
-const BuildId = std.Build.CompileStep.BuildId;
 const Cache = std.Build.Cache;
 const target_util = @import("target.zig");
 const crash_report = @import("crash_report.zig");
@@ -882,7 +881,7 @@ fn buildOutputType(
     var link_eh_frame_hdr = false;
     var link_emit_relocs = false;
     var each_lib_rpath: ?bool = null;
-    var build_id: ?BuildId = null;
+    var build_id: ?std.zig.BuildId = null;
     var sysroot: ?[]const u8 = null;
     var libc_paths_file: ?[]const u8 = try EnvVar.ZIG_LIBC.get(arena);
     var machine_code_model: std.builtin.CodeModel = .default;
@@ -1551,7 +1550,7 @@ fn buildOutputType(
                         build_id = .fast;
                     } else if (mem.startsWith(u8, arg, "--build-id=")) {
                         const style = arg["--build-id=".len..];
-                        build_id = BuildId.parse(style) catch |err| {
+                        build_id = std.zig.BuildId.parse(style) catch |err| {
                             fatal("unable to parse --build-id style '{s}': {s}", .{
                                 style, @errorName(err),
                             });
@@ -1847,7 +1846,7 @@ fn buildOutputType(
                                     const key = linker_arg[0..equals_pos];
                                     const value = linker_arg[equals_pos + 1 ..];
                                     if (mem.eql(u8, key, "--build-id")) {
-                                        build_id = BuildId.parse(value) catch |err| {
+                                        build_id = std.zig.BuildId.parse(value) catch |err| {
                                             fatal("unable to parse --build-id style '{s}': {s}", .{
                                                 value, @errorName(err),
                                             });