Replacing C-style typedefs with aliases. (#2945)

torchvision/csrc/cpu/decoder/decoder.h

@@ -7,7 +7,7 @@
 
 #if defined(_MSC_VER)
 #include <BaseTsd.h>
-typedef SSIZE_T ssize_t;
+using ssize_t = SSIZE_T;
 #endif
 
 namespace ffmpeg {

torchvision/csrc/cpu/image/jpegcommon.h

@@ -17,7 +17,7 @@ struct torch_jpeg_error_mgr {
   jmp_buf setjmp_buffer; /* for return to caller */
 };
 
-typedef struct torch_jpeg_error_mgr* torch_jpeg_error_ptr;
+using torch_jpeg_error_ptr = struct torch_jpeg_error_mgr*;
 void torch_jpeg_error_exit(j_common_ptr cinfo);
 
 #endif

torchvision/csrc/cpu/image/writepng_cpu.cpp

@@ -23,7 +23,7 @@ struct torch_png_error_mgr {
   jmp_buf setjmp_buffer; /* for return to caller */
 };
 
-typedef torch_png_error_mgr* torch_png_error_mgr_ptr;
+using torch_png_error_mgr_ptr = torch_png_error_mgr*;
 
 void torch_png_warn(png_structp png_ptr, png_const_charp warn_msg) {
   /* Display warning to user */