diff --git a/drivers/internal/Task.h b/drivers/internal/Task.h
index be2c932563c..632d690cd27 100644
--- a/drivers/internal/Task.h
+++ b/drivers/internal/Task.h
@@ -29,7 +29,7 @@ namespace events {
  */
 
 
-template<typename F, typename A1 = void, typename A2 = void, typename A3 = void, typename A4 = void, typename A5 = void>
+template<typename F, typename ARG1 = void, typename ARG2 = void, typename ARG3 = void, typename ARG4 = void, typename ARG5 = void>
 struct AllArgs;
 
 template<typename B0>
@@ -543,22 +543,22 @@ class Task<R()>: public TaskBase {
     All _args;
 };
 
-template <typename R, typename A0>
-class Task<R(A0)>: public TaskBase {
+template <typename R, typename ARG0>
+class Task<R(ARG0)>: public TaskBase {
 public:
 
-    Task(TaskQueue *q = NULL, mbed::Callback<R(A0)> cb = mbed::Callback<R(A0)>())
+    Task(TaskQueue *q = NULL, mbed::Callback<R(ARG0)> cb = mbed::Callback<R(ARG0)>())
         : TaskBase(q), _args(cb)
     {
     }
 
-    Task &operator=(mbed::Callback<R(A0)> cb)
+    Task &operator=(mbed::Callback<R(ARG0)> cb)
     {
         _args.b0 = cb;
         return *this;
     }
 
-    void call(A0 a0)
+    void call(ARG0 a0)
     {
         _args.b1 = a0;
         post();
@@ -578,7 +578,7 @@ class Task<R(A0)>: public TaskBase {
     }
 
 private:
-    typedef AllArgs<mbed::Callback<R(A0)>, A0> All;
+    typedef AllArgs<mbed::Callback<R(ARG0)>, ARG0> All;
     All _args;
 };
 
@@ -586,8 +586,8 @@ class Task<R(A0)>: public TaskBase {
  *
  *  Representation of a postable task
  */
-template <typename R, typename A0, typename A1>
-class Task<R(A0, A1)>: public TaskBase {
+template <typename R, typename ARG0, typename ARG1>
+class Task<R(ARG0, ARG1)>: public TaskBase {
 public:
 
     /**
@@ -596,7 +596,7 @@ class Task<R(A0, A1)>: public TaskBase {
      * @param q TaskQueue to post to
      * @param cb Callback to run
      */
-    Task(TaskQueue *q = NULL, mbed::Callback<R(A0, A1)> cb = mbed::Callback<R(A0, A1)>())
+    Task(TaskQueue *q = NULL, mbed::Callback<R(ARG0, ARG1)> cb = mbed::Callback<R(ARG0, ARG1)>())
         : TaskBase(q), _args(cb)
     {
     }
@@ -606,7 +606,7 @@ class Task<R(A0, A1)>: public TaskBase {
      *
      * @param cb Callback to run
      */
-    Task &operator=(mbed::Callback<R(A0, A1)> cb)
+    Task &operator=(mbed::Callback<R(ARG0, ARG1)> cb)
     {
         _args.b0 = cb;
         return *this;
@@ -623,7 +623,7 @@ class Task<R(A0, A1)>: public TaskBase {
      * @param a0 First callback parameter
      * @param a1 Second callback parameter
      */
-    void call(A0 a0, A1 a1)
+    void call(ARG0 a0, ARG1 a1)
     {
         _args.b1 = a0;
         _args.b2 = a1;
@@ -644,7 +644,7 @@ class Task<R(A0, A1)>: public TaskBase {
     }
 
 private:
-    typedef AllArgs<mbed::Callback<R(A0, A1)>, A0, A1> All;
+    typedef AllArgs<mbed::Callback<R(ARG0, ARG1)>, ARG0, ARG1> All;
     All _args;
 };
 
diff --git a/platform/FunctionPointer.h b/platform/FunctionPointer.h
index 7111b8d19bf..dfcc7becd2e 100644
--- a/platform/FunctionPointer.h
+++ b/platform/FunctionPointer.h
@@ -32,37 +32,37 @@ namespace mbed {
 
 // Declarations for backwards compatibility
 // To be foward compatible, code should adopt the Callback class
-template <typename R, typename A1>
-class FunctionPointerArg1 : public Callback<R(A1)> {
+template <typename R, typename ARG1>
+class FunctionPointerArg1 : public Callback<R(ARG1)> {
 public:
     MBED_DEPRECATED_SINCE("mbed-os-5.1",
                           "FunctionPointerArg1<R, A> has been replaced by Callback<R(A)>")
-    FunctionPointerArg1(R(*function)(A1) = 0)
-        : Callback<R(A1)>(function) {}
+    FunctionPointerArg1(R(*function)(ARG1) = 0)
+        : Callback<R(ARG1)>(function) {}
 
     template<typename T>
     MBED_DEPRECATED_SINCE("mbed-os-5.1",
                           "FunctionPointerArg1<R, A> has been replaced by Callback<R(A)>")
-    FunctionPointerArg1(T *object, R(T::*member)(A1))
-        : Callback<R(A1)>(object, member) {}
+    FunctionPointerArg1(T *object, R(T::*member)(ARG1))
+        : Callback<R(ARG1)>(object, member) {}
 
-    R(*get_function())(A1)
+    R(*get_function())(ARG1)
     {
-        return *reinterpret_cast<R(* *)(A1)>(this);
+        return *reinterpret_cast<R(* *)(ARG1)>(this);
     }
 
-    R call(A1 a1) const
+    R call(ARG1 a1) const
     {
-        if (!Callback<R(A1)>::operator bool()) {
+        if (!Callback<R(ARG1)>::operator bool()) {
             return (R)0;
         }
 
-        return Callback<R(A1)>::call(a1);
+        return Callback<R(ARG1)>::call(a1);
     }
 
-    R operator()(A1 a1) const
+    R operator()(ARG1 a1) const
     {
-        return Callback<R(A1)>::call(a1);
+        return Callback<R(ARG1)>::call(a1);
     }
 };