diff --git a/SDL_stbimage.h b/SDL_stbimage.h
index 9cab669..b7d914d 100644
--- a/SDL_stbimage.h
+++ b/SDL_stbimage.h
@@ -456,7 +456,7 @@ static int _STBIMG_io_read(void* user, char* data, int size)
 {
 	STBIMG_stbio_RWops* io = (STBIMG_stbio_RWops*)user;
 
-	int ret = _STBIMG_RWread(io->src, data, size*sizeof(char));
+	size_t ret = _STBIMG_RWread(io->src, data, size*sizeof(char));
 	if(ret == 0)
 	{
 		// we're at EOF or some error happend
@@ -640,7 +640,7 @@ SDL_STBIMG_DEF SDL_Surface* STBIMG_Load_RW_noSeek(_STBIMG_RWops* src, bool frees
 		goto end;
 	}
 
-	buf = (unsigned char*)SDL_malloc(fileSize);
+	buf = (unsigned char*)SDL_malloc((size_t)fileSize);
 	if(buf == NULL)
 	{
 		SDL_SetError("STBIMG_Load_RW_noSeek(): Couldn't allocate buffer to read src into!");
@@ -648,7 +648,7 @@ SDL_STBIMG_DEF SDL_Surface* STBIMG_Load_RW_noSeek(_STBIMG_RWops* src, bool frees
 	}
 
 	while(bytesRead < fileSize) {
-		size_t read = _STBIMG_RWread(src, buf+bytesRead, fileSize-bytesRead);
+		size_t read = _STBIMG_RWread(src, buf+bytesRead, (size_t)(fileSize-bytesRead));
 		if(read == 0) {
 			// TODO: set error? SDL_RWread/SDL_ReadIO should set one, I think?
 			goto end;
@@ -658,7 +658,7 @@ SDL_STBIMG_DEF SDL_Surface* STBIMG_Load_RW_noSeek(_STBIMG_RWops* src, bool frees
 
 	// if that fails, STBIMG_LoadFromMemory() has set an SDL error
 	// and ret is NULL, so nothing special to do for us
-	ret = STBIMG_LoadFromMemory(buf, fileSize);
+	ret = STBIMG_LoadFromMemory(buf, (int)fileSize);
 
 end:
 	if(freesrc)