auto merge of #8595 : vadimcn/rust/print_link_args, r=alexcrichton

This resolves issue #8569

Author: bors

src/librustc/back/link.rs

@@ -26,6 +26,7 @@ use std::c_str::ToCStr;
 use std::char;
 use std::hash::Streaming;
 use std::hash;
+use std::io;
 use std::libc::{c_int, c_uint};
 use std::os::consts::{macos, freebsd, linux, android, win32};
 use std::os;
@@ -858,6 +859,10 @@ pub fn link_binary(sess: Session,
     debug!("output: %s", output.to_str());
     let cc_args = link_args(sess, obj_filename, out_filename, lm);
     debug!("%s link args: %s", cc_prog, cc_args.connect(" "));
+    if (sess.opts.debugging_opts & session::print_link_args) != 0 {
+        io::println(fmt!("%s link args: %s", cc_prog, cc_args.connect(" ")));
+    }
+
     // We run 'cc' here
     let prog = run::process_output(cc_prog, cc_args);
     if 0 != prog.status {