From b6aba2f985103c7848550cd35e673d65c50fa682 Mon Sep 17 00:00:00 2001
From: Pharap <2933055+Pharap@users.noreply.github.com>
Date: Thu, 10 Jan 2019 21:16:13 +0000
Subject: [PATCH] Fix bug in templated attach function

The arguments passed to `Callback<void()>`'s constructor were the wrong way round,
thus preventing the `attach` function from being instantiated.
This patch corrects that by switching the order of the arguments.
---
 features/unsupported/USBDevice/USBSerial/USBSerial.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/features/unsupported/USBDevice/USBSerial/USBSerial.h b/features/unsupported/USBDevice/USBSerial/USBSerial.h
index 69ed61abf5..b2ad0d51df 100644
--- a/features/unsupported/USBDevice/USBSerial/USBSerial.h
+++ b/features/unsupported/USBDevice/USBSerial/USBSerial.h
@@ -126,8 +126,8 @@ public:
      */
     template<typename T>
     void attach(T* tptr, void (T::*mptr)(void)) {
-        if((mptr != NULL) && (tptr != NULL)) {
-            rx = Callback<void()>(mptr, tptr);
+        if((tptr != NULL) && (mptr != NULL)) {
+            rx = Callback<void()>(tptr, mptr);
         }
     }