diff --git a/host/hackrf-tools/CMakeLists.txt b/host/hackrf-tools/CMakeLists.txt
index 8bf2a068..bb3a4193 100644
--- a/host/hackrf-tools/CMakeLists.txt
+++ b/host/hackrf-tools/CMakeLists.txt
@@ -32,6 +32,7 @@ set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/../cmake/modules)
 
 if(MSVC)
 include_directories(getopt)
+add_definitions(/D _CRT_SECURE_NO_WARNINGS)
 else()
 add_definitions(-Wall)
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=gnu90")
diff --git a/host/hackrf-tools/src/hackrf_cpldjtag.c b/host/hackrf-tools/src/hackrf_cpldjtag.c
index 5e0bfcb0..fe3bce23 100644
--- a/host/hackrf-tools/src/hackrf_cpldjtag.c
+++ b/host/hackrf-tools/src/hackrf_cpldjtag.c
@@ -31,7 +31,11 @@
 #include <stdint.h>
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
 #endif
 /* input file shouldn't be any longer than this */
 #define MAX_XSVF_LENGTH 0x10000
diff --git a/host/hackrf-tools/src/hackrf_max2837.c b/host/hackrf-tools/src/hackrf_max2837.c
index ced59a48..d8fb75f5 100644
--- a/host/hackrf-tools/src/hackrf_max2837.c
+++ b/host/hackrf-tools/src/hackrf_max2837.c
@@ -64,7 +64,7 @@ int parse_int(char* s, uint16_t* const value) {
 	s_end = s;
 	long_value = strtol(s, &s_end, base);
 	if( (s != s_end) && (*s_end == 0) ) {
-		*value = long_value;
+		*value = (uint16_t)long_value;
 		return HACKRF_SUCCESS;
 	} else {
 		return HACKRF_ERROR_INVALID_PARAM;
@@ -73,7 +73,7 @@ int parse_int(char* s, uint16_t* const value) {
 
 int dump_register(hackrf_device* device, const uint16_t register_number) {
 	uint16_t register_value;
-	int result = hackrf_max2837_read(device, register_number, &register_value);
+	int result = hackrf_max2837_read(device, (uint8_t)register_number, &register_value);
 	
 	if( result == HACKRF_SUCCESS ) {
 		printf("[%2d] -> 0x%03x\n", register_number, register_value);
@@ -104,7 +104,7 @@ int write_register(
 	const uint16_t register_value
 ) {
 	int result = HACKRF_SUCCESS;
-	result = hackrf_max2837_write(device, register_number, register_value);
+	result = hackrf_max2837_write(device, (uint8_t)register_number, register_value);
 	
 	if( result == HACKRF_SUCCESS ) {
 		printf("0x%03x -> [%2d]\n", register_value, register_number);
diff --git a/host/hackrf-tools/src/hackrf_rffc5071.c b/host/hackrf-tools/src/hackrf_rffc5071.c
index b5409809..c9630dd4 100644
--- a/host/hackrf-tools/src/hackrf_rffc5071.c
+++ b/host/hackrf-tools/src/hackrf_rffc5071.c
@@ -65,7 +65,7 @@ int parse_int(char* s, uint16_t* const value) {
 	s_end = s;
 	long_value = strtol(s, &s_end, base);
 	if( (s != s_end) && (*s_end == 0) ) {
-		*value = long_value;
+		*value = (uint16_t)long_value;
 		return HACKRF_SUCCESS;
 	} else {
 		return HACKRF_ERROR_INVALID_PARAM;
@@ -74,7 +74,7 @@ int parse_int(char* s, uint16_t* const value) {
 
 int dump_register(hackrf_device* device, const uint16_t register_number) {
 	uint16_t register_value;
-	int result = hackrf_rffc5071_read(device, register_number, &register_value);
+	int result = hackrf_rffc5071_read(device, (uint8_t)register_number, &register_value);
 	
 	if( result == HACKRF_SUCCESS ) {
 		printf("[%2d] -> 0x%03x\n", register_number, register_value);
@@ -105,7 +105,7 @@ int write_register(
 	const uint16_t register_value
 ) {
 	int result = HACKRF_SUCCESS;
-	result = hackrf_rffc5071_write(device, register_number, register_value);
+	result = hackrf_rffc5071_write(device, (uint8_t)register_number, register_value);
 	
 	if( result == HACKRF_SUCCESS ) {
 		printf("0x%03x -> [%2d]\n", register_value, register_number);
diff --git a/host/hackrf-tools/src/hackrf_si5351c.c b/host/hackrf-tools/src/hackrf_si5351c.c
index 666ac7e4..41146f2c 100644
--- a/host/hackrf-tools/src/hackrf_si5351c.c
+++ b/host/hackrf-tools/src/hackrf_si5351c.c
@@ -49,7 +49,7 @@ int parse_int(char* const s, uint16_t* const value) {
 	char* s_end = s;
 	const long long_value = strtol(s, &s_end, 10);
 	if( (s != s_end) && (*s_end == 0) ) {
-		*value = long_value;
+		*value = (uint16_t)long_value;
 		return HACKRF_SUCCESS;
 	} else {
 		return HACKRF_ERROR_INVALID_PARAM;
diff --git a/host/hackrf-tools/src/hackrf_spiflash.c b/host/hackrf-tools/src/hackrf_spiflash.c
index f97f2875..ba2c224e 100644
--- a/host/hackrf-tools/src/hackrf_spiflash.c
+++ b/host/hackrf-tools/src/hackrf_spiflash.c
@@ -36,7 +36,11 @@ typedef int bool;
 #endif
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
 #endif
 
 /* 8 Mbit flash */
diff --git a/host/hackrf-tools/src/hackrf_transfer.c b/host/hackrf-tools/src/hackrf_transfer.c
index 2f505dc6..0f2923a3 100644
--- a/host/hackrf-tools/src/hackrf_transfer.c
+++ b/host/hackrf-tools/src/hackrf_transfer.c
@@ -43,7 +43,13 @@ typedef int bool;
 #include <windows.h>
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
+
 #define strtoull _strtoui64
 #define snprintf _snprintf
 
@@ -216,7 +222,7 @@ int parse_u32(char* s, uint32_t* const value) {
 	s_end = s;
 	ulong_value = strtoul(s, &s_end, base);
 	if( (s != s_end) && (*s_end == 0) ) {
-		*value = ulong_value;
+		*value = (uint32_t)ulong_value;
 		return HACKRF_SUCCESS;
 	} else {
 		return HACKRF_ERROR_INVALID_PARAM;
@@ -261,7 +267,7 @@ int rx_callback(hackrf_transfer* transfer) {
 		bytes_to_write = transfer->valid_length;
 		if (limit_num_samples) {
 			if (bytes_to_write >= bytes_to_xfer) {
-				bytes_to_write = bytes_to_xfer;
+				bytes_to_write = (int)bytes_to_xfer;
 			}
 			bytes_to_xfer -= bytes_to_write;
 		}
@@ -293,7 +299,7 @@ int tx_callback(hackrf_transfer* transfer) {
 				 * In this condition, we probably tx some of the previous
 				 * buffer contents at the end.  :-(
 				 */
-				bytes_to_read = bytes_to_xfer;
+				bytes_to_read = (int)bytes_to_xfer;
 			}
 			bytes_to_xfer -= bytes_to_read;
 		}
diff --git a/host/libhackrf/src/hackrf.c b/host/libhackrf/src/hackrf.c
index e1ef7dbe..4dcc9302 100644
--- a/host/libhackrf/src/hackrf.c
+++ b/host/libhackrf/src/hackrf.c
@@ -787,7 +787,8 @@ int ADDCALL hackrf_set_sample_rate(hackrf_device* device, const double freq)
 	union {
 		uint64_t u64;
 		double d;
-	} v = { .d = freq };
+	} v;
+	v.d = freq;
 
 	e = (v.u64 >> 52) - 1023;