fix: [stb_image_write.h] implicit conversions to larger type make exp…

…licit via cast

vendor/stb_image_write/stb_image_write.h

@@ -838,7 +838,7 @@ STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const
 static void *stbiw__sbgrowf(void **arr, int increment, int itemsize)
 {
    int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1;
-   void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2);
+   void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, (unsigned long) itemsize * m + sizeof(int)*2);
    STBIW_ASSERT(p);
    if (p) {
       if (!*arr) ((int *) p)[1] = 0;
@@ -1112,7 +1112,7 @@ static void stbiw__encode_png_line(unsigned char *pixels, int stride_bytes, int
    int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes;
 
    if (type==0) {
-      memcpy(line_buffer, z, width*n);
+      memcpy(line_buffer, z, (size_t) width*n);
       return;
    }
 
@@ -1153,8 +1153,8 @@ STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int s
       force_filter = -1;
    }
 
-   filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0;
-   line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
+   filt = (unsigned char *) STBIW_MALLOC((size_t) (x*n+1) * y); if (!filt) return 0;
+   line_buffer = (signed char *) STBIW_MALLOC((size_t) x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
    for (j=0; j < y; ++j) {
       int filter_type;
       if (force_filter > -1) {
@@ -1182,7 +1182,7 @@ STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int s
       }
       // when we get here, filter_type contains the filter type, and line_buffer contains the data
       filt[j*(x*n+1)] = (unsigned char) filter_type;
-      STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n);
+      STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, (size_t) x*n);
    }
    STBIW_FREE(line_buffer);
    zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level);