main: call gcc to make out executable

.gitignore

@@ -2,3 +2,4 @@ zig-cache/
 *.bc
 *.ll
 *.o
+*.out

src/main.zig

@@ -59,6 +59,13 @@ pub fn run(allocator: *std.mem.Allocator, slice: []const u8) !Result {
     var cgen = codegen.Codegen.init(allocator, &ctx);
     try cgen.gen(root);
 
+    var child = try std.ChildProcess.init(
+        [_][]const u8{ "gcc", "src/entry.c", "outpath.o", "-o", "a.out" },
+        allocator,
+    );
+    try child.spawn();
+    _ = try child.wait();
+
     return Result.Ok;
 }