A single approach was used to suppress the msvc C4996 compiler warning [_CRT_SECURE_NO_WARNINGS] (#2208)

benchmark/CMakeLists.txt

@@ -1,3 +1,9 @@
+
+if(MSVC)
+    # warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
+    add_definitions(/wd4996)
+endif()
+
 add_executable(benchncnn benchncnn.cpp)
 target_link_libraries(benchncnn PRIVATE ncnn)
 

benchmark/benchncnn.cpp

@@ -12,10 +12,6 @@
 // CONDITIONS OF ANY KIND, either express or implied. See the License for the
 // specific language governing permissions and limitations under the License.
 
-#ifdef _WIN32
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-
 #include <float.h>
 #include <stdio.h>
 #include <string.h>

tests/CMakeLists.txt

@@ -1,4 +1,9 @@
 
+if(MSVC)
+    # warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
+    add_definitions(/wd4996)
+endif()
+
 macro(ncnn_add_test name)
     add_executable(test_${name} test_${name}.cpp)
     target_link_libraries(test_${name} PRIVATE ncnn)