diff --git a/include/ntapi/nt_sysinfo.h b/include/ntapi/nt_sysinfo.h
index 3f57a43..aa6cb6e 100644
--- a/include/ntapi/nt_sysinfo.h
+++ b/include/ntapi/nt_sysinfo.h
@@ -437,7 +437,7 @@ typedef struct _nt_system_handle_information {
 	uint16_t	handle;
 	void *		object;
 	uint32_t	granted_access;
-#if defined (__NT64)
+#if (__SIZEOF_POINTER__ == 8)
 	uint32_t	granted_access_padding;
 #endif
 } nt_system_handle_information;
diff --git a/src/process/ntapi_tt_create_native_process_v1.c b/src/process/ntapi_tt_create_native_process_v1.c
index f17f236..a44ed4f 100644
--- a/src/process/ntapi_tt_create_native_process_v1.c
+++ b/src/process/ntapi_tt_create_native_process_v1.c
@@ -52,11 +52,11 @@ int32_t __stdcall __ntapi_tt_create_native_process_v1(nt_create_process_params *
 	size_t				cmd_line_runtime_buffer_size;
 	int				fresume_thread;
 
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 	wchar16_t		runtime_arg[12] = {
 		' ','-','r',' ',
 		'i','n','t','e','g','r','a','l'};
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 	wchar16_t		runtime_arg[20] = {
 		' ','-','r',' ',
 		'i','n','t','e','g','r','a','l',
diff --git a/src/process/ntapi_tt_create_native_process_v2.c b/src/process/ntapi_tt_create_native_process_v2.c
index 2d058a0..f28a522 100644
--- a/src/process/ntapi_tt_create_native_process_v2.c
+++ b/src/process/ntapi_tt_create_native_process_v2.c
@@ -49,11 +49,11 @@ int32_t __stdcall __ntapi_tt_create_native_process_v2(
 		nt_create_process_ext_param	file_info;
 	} ext_params;
 
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 	wchar16_t		runtime_arg[12] = {
 		' ','-','r',' ',
 		'i','n','t','e','g','r','a','l'};
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 	wchar16_t		runtime_arg[20] = {
 		' ','-','r',' ',
 		'i','n','t','e','g','r','a','l',
diff --git a/src/process/ntapi_tt_create_remote_runtime_data.c b/src/process/ntapi_tt_create_remote_runtime_data.c
index b3809b0..7b85893 100644
--- a/src/process/ntapi_tt_create_remote_runtime_data.c
+++ b/src/process/ntapi_tt_create_remote_runtime_data.c
@@ -26,10 +26,10 @@ int32_t __stdcall __ntapi_tt_create_remote_runtime_data(
 	nt_runtime_data *	rtdata;
 	void *			srv_ready;
 
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 	wchar16_t		runtime_arg[8] = {
 		'i','n','t','e','g','r','a','l'};
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 	wchar16_t		runtime_arg[16] = {
 		'i','n','t','e','g','r','a','l',
 		'-','r','u','n','t','i','m','e'};
diff --git a/src/process/ntapi_tt_get_runtime_data.c b/src/process/ntapi_tt_get_runtime_data.c
index 5dc2366..60cdf17 100644
--- a/src/process/ntapi_tt_get_runtime_data.c
+++ b/src/process/ntapi_tt_get_runtime_data.c
@@ -10,11 +10,11 @@
 #include <ntapi/ntapi.h>
 #include "ntapi_impl.h"
 
-#if defined (__NT32)
+#if (__SIZEOF_POINTER__ == 4)
 static wchar16_t runtime_arg[12] = {
 	' ','-','r',' ',
 	'i','n','t','e','g','r','a','l'};
-#elif defined (__NT64)
+#elif (__SIZEOF_POINTER__ == 8)
 static wchar16_t runtime_arg[20] = {
 	' ','-','r',' ',
 	'i','n','t','e','g','r','a','l',
diff --git a/src/string/ntapi_tt_hex_utf16_to_uintptr.c b/src/string/ntapi_tt_hex_utf16_to_uintptr.c
index 494e5ef..0edc870 100644
--- a/src/string/ntapi_tt_hex_utf16_to_uintptr.c
+++ b/src/string/ntapi_tt_hex_utf16_to_uintptr.c
@@ -94,9 +94,9 @@ int32_t __fastcall __ntapi_tt_hex_utf16_to_uintptr(
 	__in	wchar16_t	hex_key_utf16[],
 	__out	uintptr_t *	key)
 {
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 		return __ntapi_tt_hex_utf16_to_uint32(hex_key_utf16,key);
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 		return __ntapi_tt_hex_utf16_to_uint64(hex_key_utf16,key);
 	#endif
 }
diff --git a/src/string/ntapi_tt_uintptr_to_hex_utf16.c b/src/string/ntapi_tt_uintptr_to_hex_utf16.c
index bb7ae8c..2cd0b69 100644
--- a/src/string/ntapi_tt_uintptr_to_hex_utf16.c
+++ b/src/string/ntapi_tt_uintptr_to_hex_utf16.c
@@ -73,12 +73,12 @@ void __fastcall __ntapi_tt_uintptr_to_hex_utf16(
 	__in	uintptr_t	key,
 	__out	wchar16_t *	formatted_key)
 {
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 		__ntapi_tt_uint_to_hex_utf16(
 			key,
 			formatted_key,
 			32);
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 		__ntapi_tt_uint_to_hex_utf16(
 			key,
 			formatted_key,
diff --git a/src/string/ntapi_tt_uintptr_to_hex_utf8.c b/src/string/ntapi_tt_uintptr_to_hex_utf8.c
index 7fb1dc5..d18725b 100644
--- a/src/string/ntapi_tt_uintptr_to_hex_utf8.c
+++ b/src/string/ntapi_tt_uintptr_to_hex_utf8.c
@@ -65,9 +65,9 @@ void __fastcall __ntapi_tt_uintptr_to_hex_utf8(
 	__in	uintptr_t	key,
 	__out	unsigned char *	buffer)
 {
-	#if defined (__NT32)
+	#if (__SIZEOF_POINTER__ == 4)
 		__ntapi_tt_uint_to_hex_utf8(key,buffer,32);
-	#elif defined (__NT64)
+	#elif (__SIZEOF_POINTER__ == 8)
 		__ntapi_tt_uint_to_hex_utf8(key,buffer,64);
 	#endif
 }