tools/tiffcrop.c:7333: error: Null Dereference
  pointer `sect_buff` last assigned on line 7331 could be null and is dereferenced by call to `_TIFFmemset()` at line 7333, column 5.

tools/tiffcrop.c:7320:1: start of procedure createImageSection()
7318. 
7319. /* Create a buffer to write one section at a time */
7320. static int
      ^
7321. createImageSection(uint32 sectsize, unsigned char **sect_buff_ptr)
7322.   {

tools/tiffcrop.c:7323:3: 
7321. createImageSection(uint32 sectsize, unsigned char **sect_buff_ptr)
7322.   {
7323.   unsigned  char *sect_buff = NULL;
        ^
7324.   unsigned  char *new_buff  = NULL;
7325.   static    uint32  prev_sectsize = 0;

tools/tiffcrop.c:7324:3: 
7322.   {
7323.   unsigned  char *sect_buff = NULL;
7324.   unsigned  char *new_buff  = NULL;
        ^
7325.   static    uint32  prev_sectsize = 0;
7326.   

tools/tiffcrop.c:7325:3: 
7323.   unsigned  char *sect_buff = NULL;
7324.   unsigned  char *new_buff  = NULL;
7325.   static    uint32  prev_sectsize = 0;
        ^
7326.   
7327.   sect_buff = *sect_buff_ptr;

tools/tiffcrop.c:7327:3: 
7325.   static    uint32  prev_sectsize = 0;
7326.   
7327.   sect_buff = *sect_buff_ptr;
        ^
7328. 
7329.   if (!sect_buff)

tools/tiffcrop.c:7329:8: Taking true branch
7327.   sect_buff = *sect_buff_ptr;
7328. 
7329.   if (!sect_buff)
             ^
7330.     {
7331.     sect_buff = (unsigned char *)_TIFFmalloc(sectsize);

tools/tiffcrop.c:7331:5: 
7329.   if (!sect_buff)
7330.     {
7331.     sect_buff = (unsigned char *)_TIFFmalloc(sectsize);
          ^
7332.     *sect_buff_ptr = sect_buff;
7333.     _TIFFmemset(sect_buff, 0, sectsize);

libtiff/tif_unix.c:308:1: start of procedure _TIFFmalloc()
  306. #endif
  307. 
  308. void*
       ^
  309. _TIFFmalloc(tmsize_t s)
  310. {

libtiff/tif_unix.c:311:13: Taking false branch
  309. _TIFFmalloc(tmsize_t s)
  310. {
  311.         if (s == 0)
                   ^
  312.                 return ((void *) NULL);
  313. 

libtiff/tif_unix.c:314:2: 
  312.                 return ((void *) NULL);
  313. 
  314. 	return (malloc((size_t) s));
        ^
  315. }
  316. 

libtiff/tif_unix.c:315:1: return from a call to _TIFFmalloc
  313. 
  314. 	return (malloc((size_t) s));
  315. }
       ^
  316. 
  317. void* _TIFFcalloc(tmsize_t nmemb, tmsize_t siz)

tools/tiffcrop.c:7332:5: 
7330.     {
7331.     sect_buff = (unsigned char *)_TIFFmalloc(sectsize);
7332.     *sect_buff_ptr = sect_buff;
          ^
7333.     _TIFFmemset(sect_buff, 0, sectsize);
7334.     }

tools/tiffcrop.c:7333:5: 
7331.     sect_buff = (unsigned char *)_TIFFmalloc(sectsize);
7332.     *sect_buff_ptr = sect_buff;
7333.     _TIFFmemset(sect_buff, 0, sectsize);
          ^
7334.     }
7335.   else

libtiff/tif_unix.c:337:1: start of procedure _TIFFmemset()
  335. }
  336. 
  337. void
       ^
  338. _TIFFmemset(void* p, int v, tmsize_t c)
  339. {

libtiff/tif_unix.c:340:2: 
  338. _TIFFmemset(void* p, int v, tmsize_t c)
  339. {
  340. 	memset(p, v, (size_t) c);
        ^
  341. }
  342. 

libtiff/tif_unix.c:341:1: return from a call to _TIFFmemset
  339. {
  340. 	memset(p, v, (size_t) c);
  341. }
       ^
  342. 
  343. void
