diff --git a/src/Makefile b/src/Makefile
index 031e30b4..c801897b 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -4,12 +4,10 @@
 # Copyright (C) 1996-2016 Markus Franz Xaver Johannes Oberhumer
 #
 
-# In GNU Make 4.0 this "MAKEFLAGS += -rR" is not executed immediately.
-# Instead, it is executed later, and we cannot rely on sequentiality
-# with respect to builtin variables.  So if we want to have no
-# dependencies on the default values of builtin variables,
-# then we cannot use builtin variables at all.
-# See: http://lists.gnu.org/archive/html/help-make/2016-08/msg00011.html
+# build configuration options
+#USE_DEBUG = 1
+#USE_SANITIZE = 1
+
 MAKEFLAGS += -r
 ifneq ($(upx_CXX),)
 CXX = $(upx_CXX)
@@ -20,10 +18,6 @@ else
 CXXLD = $(CXX)
 endif
 
-# build configuration options
-#USE_DEBUG = 1
-#USE_SANITIZE = 1
-
 .SUFFIXES:
 export SHELL = /bin/sh
 override e = $($1) $(EXTRA_$1) $(upx_$1) $($(basename $(notdir $@)).$1)
@@ -104,7 +98,7 @@ ifeq (1,1)
 	@echo "Updating $@"
 	@$(strip $(CXX) $(call e,CPPFLAGS) -MM) $(filter %.cpp,$^) > $@
 else
-	touch $@
+	@echo "timestamp" > $@
 endif
 
 
diff --git a/src/conf.h b/src/conf.h
index d06d9862..8f854b43 100644
--- a/src/conf.h
+++ b/src/conf.h
@@ -66,11 +66,6 @@
 #define ACC_WANT_ACC_LIB_H 1
 #define ACC_WANT_ACC_CXX_H 1
 #include "miniacc.h"
-#if (ACC_OS_CYGWIN || ACC_OS_DOS16 || ACC_OS_DOS32 || ACC_OS_EMX || ACC_OS_OS2 || ACC_OS_OS216 || ACC_OS_WIN16 || ACC_OS_WIN32 || ACC_OS_WIN64)
-#  if defined(INVALID_HANDLE_VALUE) || defined(MAKEWORD) || defined(RT_CURSOR)
-#    error "something pulled in <windows.h>"
-#  endif
-#endif
 
 /* intergral types */
 typedef acc_int8_t      upx_int8_t;
@@ -89,7 +84,7 @@ typedef acc_uintptr_t   upx_uintptr_t;
 #define UPX_INT64_C     ACC_INT64_C
 #define UPX_UINT64_C    ACC_UINT64_C
 
-#define upx_byte        unsigned char
+typedef unsigned char   upx_byte;
 #define upx_bytep       upx_byte *
 
 
@@ -615,9 +610,6 @@ struct upx_compress_result_t
 **************************************************************************/
 
 #include "snprintf.h"
-
-#if defined(__cplusplus)
-
 #include "stdcxx.h"
 #include "options.h"
 #include "except.h"
@@ -707,9 +699,6 @@ int upx_test_overlap       ( const upx_bytep buf,
                              const upx_compress_result_t *cresult );
 
 
-#endif /* __cplusplus */
-
-
 #if (ACC_OS_CYGWIN || ACC_OS_DOS16 || ACC_OS_DOS32 || ACC_OS_EMX || ACC_OS_OS2 || ACC_OS_OS216 || ACC_OS_WIN16 || ACC_OS_WIN32 || ACC_OS_WIN64)
 #  if defined(INVALID_HANDLE_VALUE) || defined(MAKEWORD) || defined(RT_CURSOR)
 #    error "something pulled in <windows.h>"
diff --git a/src/packer.cpp b/src/packer.cpp
index 8da658b5..2ea0dc10 100644
--- a/src/packer.cpp
+++ b/src/packer.cpp
@@ -1116,27 +1116,29 @@ void Packer::initLoader(const void *pdata, int plen, int small)
 
 
 #define C const char *
+#define N ACC_STATIC_CAST(void *, 0)
 void Packer::addLoader(C a)
-{ addLoaderVA(a, NULL); }
+{ addLoaderVA(a, N); }
 void Packer::addLoader(C a, C b)
-{ addLoaderVA(a, b, NULL); }
+{ addLoaderVA(a, b, N); }
 void Packer::addLoader(C a, C b, C c)
-{ addLoaderVA(a, b, c, NULL); }
+{ addLoaderVA(a, b, c, N); }
 void Packer::addLoader(C a, C b, C c, C d)
-{ addLoaderVA(a, b, c, d, NULL); }
+{ addLoaderVA(a, b, c, d, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e)
-{ addLoaderVA(a, b, c, d, e, NULL); }
+{ addLoaderVA(a, b, c, d, e, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e, C f)
-{ addLoaderVA(a, b, c, d, e, f, NULL); }
+{ addLoaderVA(a, b, c, d, e, f, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e, C f, C g)
-{ addLoaderVA(a, b, c, d, e, f, g, NULL); }
+{ addLoaderVA(a, b, c, d, e, f, g, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e, C f, C g, C h)
-{ addLoaderVA(a, b, c, d, e, f, g, h, NULL); }
+{ addLoaderVA(a, b, c, d, e, f, g, h, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e, C f, C g, C h, C i)
-{ addLoaderVA(a, b, c, d, e, f, g, h, i, NULL); }
+{ addLoaderVA(a, b, c, d, e, f, g, h, i, N); }
 void Packer::addLoader(C a, C b, C c, C d, C e, C f, C g, C h, C i, C j)
-{ addLoaderVA(a, b, c, d, e, f, g, h, i, j, NULL); }
+{ addLoaderVA(a, b, c, d, e, f, g, h, i, j, N); }
 #undef C
+#undef N
 
 void __acc_cdecl_va Packer::addLoaderVA(const char *s, ...)
 {