From 442bcbfaf2ab0db8bc2890d44f8829224038ecdd Mon Sep 17 00:00:00 2001
From: Ivan Maidanski <ivmai@mail.ru>
Date: Thu, 20 Apr 2017 11:17:20 +0300
Subject: [PATCH] Eliminate 'unused formal parameter' compiler warnings in C++
 code (MS VC)

* include/gc_allocator.h (GC_ATTR_UNUSED): Remove.
* tests/test_cpp.cc (ATTR_UNUSED): Likewise.
* include/gc_allocator.h (gc_allocator::deallocate,
gc_allocator_ignore_off_page::deallocate,
traceable_allocator::deallocate): Comment out unused argument name
instead of using GC_ATTR_UNUSED.
* include/gc_cpp.h [_MSC_VER && !GC_DEBUG] (operator new): Comment out
unused argument names.
* tests/test_cpp.cc [(MSWIN32 && !__MINGW32__ || MSWINCE)
&& !NO_WINMAIN_ENTRY] (WinMain): Comment out unused argument names
instead of using ATTR_UNUSED.
---
 include/gc_allocator.h | 12 +++---------
 include/gc_cpp.h       | 20 ++++++++++++--------
 tests/test_cpp.cc      | 11 ++---------
 3 files changed, 17 insertions(+), 26 deletions(-)

diff --git a/include/gc_allocator.h b/include/gc_allocator.h
index 3ea80a07..9d70ed5a 100644
--- a/include/gc_allocator.h
+++ b/include/gc_allocator.h
@@ -44,12 +44,6 @@
 #include "gc.h"
 #include <new> // for placement new
 
-#if defined(__GNUC__)
-#  define GC_ATTR_UNUSED __attribute__((__unused__))
-#else
-#  define GC_ATTR_UNUSED
-#endif
-
 #ifndef GC_ATTR_EXPLICIT
 # if (__cplusplus >= 201103L) || defined(CPPCHECK)
 #   define GC_ATTR_EXPLICIT explicit
@@ -142,7 +136,7 @@ public:
   }
 
   // __p is not permitted to be a null pointer.
-  void deallocate(pointer __p, size_type GC_ATTR_UNUSED GC_n)
+  void deallocate(pointer __p, size_type /* GC_n */)
     { GC_FREE(__p); }
 
   size_type max_size() const throw()
@@ -219,7 +213,7 @@ public:
   }
 
   // __p is not permitted to be a null pointer.
-  void deallocate(pointer __p, size_type GC_ATTR_UNUSED GC_n)
+  void deallocate(pointer __p, size_type /* GC_n */)
     { GC_FREE(__p); }
 
   size_type max_size() const throw()
@@ -295,7 +289,7 @@ public:
   }
 
   // __p is not permitted to be a null pointer.
-  void deallocate(pointer __p, size_type GC_ATTR_UNUSED GC_n)
+  void deallocate(pointer __p, size_type /* GC_n */)
     { GC_FREE(__p); }
 
   size_type max_size() const throw()
diff --git a/include/gc_cpp.h b/include/gc_cpp.h
index 920b8368..d41a0f52 100644
--- a/include/gc_cpp.h
+++ b/include/gc_cpp.h
@@ -306,15 +306,19 @@ inline void* operator new(size_t size, GC_NS_QUALIFY(GCPlacement) gcp,
   }
 
   // This new operator is used by VC++ in case of Debug builds:
-  inline void* operator new(size_t size, int /* nBlockUse */,
-                            const char* szFileName, int nLine)
-  {
-#   ifndef GC_DEBUG
-      return GC_malloc_uncollectable(size);
-#   else
+# ifdef GC_DEBUG
+    inline void* operator new(size_t size, int /* nBlockUse */,
+                              const char* szFileName, int nLine)
+    {
       return GC_debug_malloc_uncollectable(size, szFileName, nLine);
-#   endif
-  }
+    }
+# else
+    inline void* operator new(size_t size, int /* nBlockUse */,
+                              const char* /* szFileName */, int /* nLine */)
+    {
+      return GC_malloc_uncollectable(size);
+    }
+# endif /* !GC_DEBUG */
 
 # if _MSC_VER > 1020
     // This new operator is used by VC++ 7+ in Debug builds:
diff --git a/tests/test_cpp.cc b/tests/test_cpp.cc
index 902a8247..bb18ed54 100644
--- a/tests/test_cpp.cc
+++ b/tests/test_cpp.cc
@@ -70,12 +70,6 @@ extern "C" {
                     __LINE__ ); \
         exit( 1 ); }
 
-#if GC_GNUC_PREREQ(3, 4)
-# define ATTR_UNUSED __attribute__((__unused__))
-#else
-# define ATTR_UNUSED /* empty */
-#endif
-
 #ifndef GC_ATTR_EXPLICIT
 # if (__cplusplus >= 201103L) || defined(CPPCHECK)
 #   define GC_ATTR_EXPLICIT explicit
@@ -207,9 +201,8 @@ void* Undisguise( GC_word i ) {
 
 #if ((defined(MSWIN32) && !defined(__MINGW32__)) || defined(MSWINCE)) \
     && !defined(NO_WINMAIN_ENTRY)
-  int APIENTRY WinMain( HINSTANCE instance ATTR_UNUSED,
-                       HINSTANCE prev ATTR_UNUSED, LPSTR cmd,
-                       int cmdShow ATTR_UNUSED )
+  int APIENTRY WinMain( HINSTANCE /* instance */, HINSTANCE /* prev */,
+                       LPSTR cmd, int /* cmdShow */)
   {
     int argc = 0;
     char* argv[ 3 ];
-- 
2.40.0