diff --git a/source/lib/byte_order.h b/source/lib/byte_order.h
index cec2d9c3c0..cacc2dcac4 100644
--- a/source/lib/byte_order.h
+++ b/source/lib/byte_order.h
@@ -127,15 +127,16 @@ LIB_API i64 movsx_le64(const u8* p, size_t size);
 LIB_API i64 movsx_be64(const u8* p, size_t size);
 
 
-#if MSC_VERSION
+#if ICC_VERSION
+#define swap32 _bswap
+#define swap64 _bswap64
+#elif MSC_VERSION
 extern unsigned short _byteswap_ushort(unsigned short);
 extern unsigned long _byteswap_ulong(unsigned long);
 extern unsigned __int64 _byteswap_uint64(unsigned __int64);
-# if !ICC_VERSION	// ICC doesn't need (and warns about) the pragmas
-#  pragma intrinsic(_byteswap_ushort)
-#  pragma intrinsic(_byteswap_ulong)
-#  pragma intrinsic(_byteswap_uint64)
-# endif
+#pragma intrinsic(_byteswap_ushort)
+#pragma intrinsic(_byteswap_ulong)
+#pragma intrinsic(_byteswap_uint64)
 # define swap16 _byteswap_ushort
 # define swap32 _byteswap_ulong
 # define swap64 _byteswap_uint64
diff --git a/source/lib/code_annotation.h b/source/lib/code_annotation.h
index 2abd599ebf..101a907b71 100644
--- a/source/lib/code_annotation.h
+++ b/source/lib/code_annotation.h
@@ -27,12 +27,20 @@
 #ifndef INCLUDED_CODE_ANNOTATION
 #define INCLUDED_CODE_ANNOTATION
 
+#include "lib/sysdep/compiler.h"
+
 /**
  * mark a function local variable or parameter as unused and avoid
  * the corresponding compiler warning.
  * use inside the function body, e.g. void f(int x) { UNUSED2(x); }
  **/
-#define UNUSED2(param) (void)param;
+#if ICC_VERSION
+// NB: #pragma unused is documented but "unrecognized" when used;
+// casting to void isn't sufficient, but the following is:
+# define UNUSED2(param) param = param
+#else
+# define UNUSED2(param) (void)param
+#endif
 
 /**
  * mark a function parameter as unused and avoid
diff --git a/source/lib/sysdep/os/win/mahaf.cpp b/source/lib/sysdep/os/win/mahaf.cpp
index eb800afb25..dd23328fdb 100644
--- a/source/lib/sysdep/os/win/mahaf.cpp
+++ b/source/lib/sysdep/os/win/mahaf.cpp
@@ -218,7 +218,7 @@ static SC_HANDLE OpenServiceControlManager()
 		// Least-Permission accounts to use it, but is too invasive and
 		// thus out of the question.
 
-		// make sure the error is as expected, otherwise something is afoot.
+		// rule out other problems
 		debug_assert(GetLastError() == ERROR_ACCESS_DENIED);
 
 		return 0;
@@ -286,9 +286,10 @@ static void StartDriver(const fs::wpath& driverPathname)
 	if(!hService)
 	{
 		LPCWSTR startName = 0;	// LocalSystem
+		// NB: Windows 7 seems to insist upon backslashes (i.e. external_file_string)
 		hService = CreateServiceW(hSCM, AKEN_NAME, AKEN_NAME,
 			SERVICE_ALL_ACCESS, SERVICE_KERNEL_DRIVER, SERVICE_DEMAND_START, SERVICE_ERROR_NORMAL,
-			driverPathname.string().c_str(), 0, 0, 0, startName, 0);
+			driverPathname.external_file_string().c_str(), 0, 0, 0, startName, 0);
 		debug_assert(hService != 0);
 	}
 
@@ -302,7 +303,7 @@ static void StartDriver(const fs::wpath& driverPathname)
 			{
 				// starting failed. don't raise a warning because this
 				// always happens on least-permission user accounts.
-				//WARN_IF_FALSE(0);
+				//debug_assert(0);
 			}
 		}
 	}
@@ -340,7 +341,7 @@ static fs::wpath DriverPathname()
 static LibError Init()
 {
 	if(wutil_HasCommandLineArgument(L"-wNoMahaf"))
-		return ERR::NOT_SUPPORTED;
+		return ERR::NOT_SUPPORTED;	// NOWARN
 
 	{
 		const fs::wpath driverPathname = DriverPathname();
@@ -351,7 +352,7 @@ static LibError Init()
 		const DWORD shareMode = 0;
 		hAken = CreateFileW(L"\\\\.\\Aken", GENERIC_READ, shareMode, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
 		if(hAken == INVALID_HANDLE_VALUE)
-			return ERR::INVALID_HANDLE;
+			return ERR::INVALID_HANDLE;	// NOWARN (happens often due to security restrictions)
 	}
 
 	return INFO::OK;
@@ -365,6 +366,7 @@ static void Shutdown()
 	UninstallDriver();
 }
 
+
 static ModuleInitState initState;
 
 LibError mahaf_Init()