add objdump subcommand

does nothing so far

lib/compiler/objdump.zig

@@ -0,0 +1,33 @@
+const std = @import("std");
+const Io = std.Io;
+const fatal = std.process.fatal;
+
+pub fn main(init: std.process.Init) !void {
+    const io = init.io;
+    const args = try init.minimal.args.toSlice(init.arena.allocator());
+
+    var input_path: ?[]const u8 = null;
+    var i: usize = 0;
+    while (i < args.len) : (i += 1) {
+        const arg = args[i];
+        if (std.mem.startsWith(u8, arg, "-")) {
+            if (std.mem.eql(u8, arg, "-h") or std.mem.eql(u8, arg, "--help")) {
+                return Io.File.stdout().writeStreamingAll(io, usage);
+            } else {
+                fatal("unrecognized argument: {s}", .{arg});
+            }
+        } else if (input_path == null) {
+            input_path = arg;
+        } else {
+            fatal("unexpected positional: {s}", .{arg});
+        }
+    }
+}
+
+const usage =
+    \\Usage: zig objdump [options] file
+    \\
+    \\Options:
+    \\  -h, --help                              Print this help and exit
+    \\
+;

src/main.zig

@@ -95,13 +95,14 @@ const normal_usage =
     \\  reduce           Minimize a bug report
     \\  translate-c      Convert C code to Zig code
     \\
-    \\  ar               Use Zig as a drop-in archiver
+    \\  ar               Combine object files into static archive
     \\  cc               Use Zig as a drop-in C compiler
     \\  c++              Use Zig as a drop-in C++ compiler
     \\  dlltool          Use Zig as a drop-in dlltool.exe
     \\  lib              Use Zig as a drop-in lib.exe
+    \\  objcopy          Manipulate executables and relocatables
+    \\  objdump          Print information about executables and relocatables
     \\  ranlib           Use Zig as a drop-in ranlib
-    \\  objcopy          Use Zig as a drop-in objcopy
     \\  rc               Use Zig as a drop-in rc.exe
     \\
     \\  env              Print lib path, std path, cache directory, and version
@@ -342,6 +343,11 @@ fn mainArgs(
             .cmd_name = "objcopy",
             .root_src_path = "objcopy.zig",
         });
+    } else if (mem.eql(u8, cmd, "objdump")) {
+        return jitCmd(gpa, arena, io, cmd_args, environ_map, .{
+            .cmd_name = "objdump",
+            .root_src_path = "objdump.zig",
+        });
     } else if (mem.eql(u8, cmd, "fetch")) {
         return cmdFetch(gpa, arena, io, cmd_args, environ_map);
     } else if (mem.eql(u8, cmd, "libc")) {