std.Build: add build-id option

Author: Jan200101

lib/compiler/build_runner.zig

@@ -202,6 +202,15 @@ pub fn main() !void {
                         next_arg, @errorName(err),
                     });
                 };
+            } else if (mem.eql(u8, arg, "--build-id")) {
+                builder.build_id = .fast;
+            } else if (mem.startsWith(u8, arg, "--build-id=")) {
+                const style = arg["--build-id=".len..];
+                builder.build_id = std.zig.BuildId.parse(style) catch |err| {
+                    fatal("unable to parse --build-id style '{s}': {s}", .{
+                        style, @errorName(err),
+                    });
+                };
             } else if (mem.eql(u8, arg, "--debounce")) {
                 const next_arg = nextArg(args, &arg_idx) orelse
                     fatalWithHint("expected u16 after '{s}'", .{arg});
@@ -1351,6 +1360,10 @@ fn usage(b: *std.Build, out_stream: anytype) !void {
         \\  --zig-lib-dir [arg]          Override path to Zig lib directory
         \\  --build-runner [file]        Override path to build runner
         \\  --seed [integer]             For shuffling dependency traversal order (default: random)
+        \\  --build-id[=style]             At a minor link-time expense, coordinates stripped binaries
+        \\      fast, uuid, sha1, md5      with debug symbols via a '.note.gnu.build-id' section
+        \\      0x[hexstring]              Maximum 32 bytes
+        \\      none                       (default) Disable build-id
         \\  --debug-log [scope]          Enable debugging the compiler
         \\  --debug-pkg-config           Fail if unknown pkg-config flags encountered
         \\  --debug-rt                   Debug compiler runtime libraries

lib/std/Build.zig

@@ -94,6 +94,8 @@ available_deps: AvailableDeps,
 
 release_mode: ReleaseMode,
 
+build_id: ?std.zig.BuildId = null,
+
 pub const ReleaseMode = enum {
     off,
     any,

lib/std/Build/Step/Compile.zig

@@ -1664,7 +1664,7 @@ fn getZigArgs(compile: *Compile, fuzz: bool) ![][]const u8 {
 
     try addFlag(&zig_args, "each-lib-rpath", compile.each_lib_rpath);
 
-    if (compile.build_id) |build_id| {
+    if (compile.build_id orelse b.build_id) |build_id| {
         try zig_args.append(switch (build_id) {
             .hexstring => |hs| b.fmt("--build-id=0x{s}", .{
                 std.fmt.fmtSliceHexLower(hs.toSlice()),