tools/tiffcrop.c:7215: error: Null Dereference
  pointer `sect_buff` last assigned on line 7210 could be null and is dereferenced by call to `_TIFFmemset()` at line 7215, column 7.

tools/tiffcrop.c:7187:1: start of procedure createImageSection()
7185. 
7186. /* Create a buffer to write one section at a time */
7187. static int
      ^
7188. createImageSection(uint32 sectsize, unsigned char **sect_buff_ptr)
7189.   {

tools/tiffcrop.c:7190:3: 
7188. createImageSection(uint32 sectsize, unsigned char **sect_buff_ptr)
7189.   {
7190.   unsigned  char *sect_buff = NULL;
        ^
7191.   unsigned  char *new_buff  = NULL;
7192.   static    uint32  prev_sectsize = 0;

tools/tiffcrop.c:7191:3: 
7189.   {
7190.   unsigned  char *sect_buff = NULL;
7191.   unsigned  char *new_buff  = NULL;
        ^
7192.   static    uint32  prev_sectsize = 0;
7193.   

tools/tiffcrop.c:7192:3: 
7190.   unsigned  char *sect_buff = NULL;
7191.   unsigned  char *new_buff  = NULL;
7192.   static    uint32  prev_sectsize = 0;
        ^
7193.   
7194.   sect_buff = *sect_buff_ptr;

tools/tiffcrop.c:7194:3: 
7192.   static    uint32  prev_sectsize = 0;
7193.   
7194.   sect_buff = *sect_buff_ptr;
        ^
7195. 
7196.   if (!sect_buff)

tools/tiffcrop.c:7196:8: Taking false branch
7194.   sect_buff = *sect_buff_ptr;
7195. 
7196.   if (!sect_buff)
             ^
7197.     {
7198.     sect_buff = (unsigned char *)_TIFFmalloc(sectsize);

tools/tiffcrop.c:7204:9: Taking true branch
7202.   else
7203.     {
7204.     if (prev_sectsize < sectsize)
              ^
7205.       {
7206.       new_buff = _TIFFrealloc(sect_buff, sectsize);

tools/tiffcrop.c:7206:7: 
7204.     if (prev_sectsize < sectsize)
7205.       {
7206.       new_buff = _TIFFrealloc(sect_buff, sectsize);
            ^
7207.       if (!new_buff)
7208.         {

libtiff/tif_unix.c:272:1: start of procedure _TIFFrealloc()
  270. }
  271. 
  272. void*
       ^
  273. _TIFFrealloc(void* p, tmsize_t s)
  274. {

libtiff/tif_unix.c:275:2: 
  273. _TIFFrealloc(void* p, tmsize_t s)
  274. {
  275. 	return (realloc(p, (size_t) s));
        ^
  276. }
  277. 

libtiff/tif_unix.c:276:1: return from a call to _TIFFrealloc
  274. {
  275. 	return (realloc(p, (size_t) s));
  276. }
       ^
  277. 
  278. void

tools/tiffcrop.c:7207:12: Taking true branch
7205.       {
7206.       new_buff = _TIFFrealloc(sect_buff, sectsize);
7207.       if (!new_buff)
                 ^
7208.         {
7209. 	free (sect_buff);

tools/tiffcrop.c:7209:2: 
7207.       if (!new_buff)
7208.         {
7209. 	free (sect_buff);
       ^
7210.         sect_buff = (unsigned char *)_TIFFmalloc(sectsize);
7211.         }

tools/tiffcrop.c:7210:9: 
7208.         {
7209. 	free (sect_buff);
7210.         sect_buff = (unsigned char *)_TIFFmalloc(sectsize);
              ^
7211.         }
7212.       else

libtiff/tif_unix.c:257:1: start of procedure _TIFFmalloc()
  255. #endif
  256. 
  257. void*
       ^
  258. _TIFFmalloc(tmsize_t s)
  259. {

libtiff/tif_unix.c:260:13: Taking false branch
  258. _TIFFmalloc(tmsize_t s)
  259. {
  260.         if (s == 0)
                   ^
  261.                 return ((void *) NULL);
  262. 

libtiff/tif_unix.c:263:2: 
  261.                 return ((void *) NULL);
  262. 
  263. 	return (malloc((size_t) s));
        ^
  264. }
  265. 

libtiff/tif_unix.c:264:1: return from a call to _TIFFmalloc
  262. 
  263. 	return (malloc((size_t) s));
  264. }
       ^
  265. 
  266. void

tools/tiffcrop.c:7215:7: 
7213.         sect_buff = new_buff;
7214. 
7215.       _TIFFmemset(sect_buff, 0, sectsize);
            ^
7216.       }
7217.     }

libtiff/tif_unix.c:278:1: start of procedure _TIFFmemset()
  276. }
  277. 
  278. void
       ^
  279. _TIFFmemset(void* p, int v, tmsize_t c)
  280. {

libtiff/tif_unix.c:281:2: 
  279. _TIFFmemset(void* p, int v, tmsize_t c)
  280. {
  281. 	memset(p, v, (size_t) c);
        ^
  282. }
  283. 

libtiff/tif_unix.c:282:1: return from a call to _TIFFmemset
  280. {
  281. 	memset(p, v, (size_t) c);
  282. }
       ^
  283. 
  284. void
