core: Silence newer compiler warnings.

* configure.ac: Add -Wno-format-truncation and
  -Wno-sizeof-pointer-div.
* src/b64dec.c (_gpgme_b64dec_proc): Add fallthrough annotation.
* src/cJSON.c (parse_string): Ditto.
* src/gpgme-json.c (main): Ditto.
--

gcc 8 enables a couple of new warnings.  Some of them are useless for
us.  In particular:

  util.h:42:26: warning: division 'sizeof (char *) / sizeof (char)'
  does not compute the number of array elements [-Wsizeof-pointer-div]
  #define DIM(v) (sizeof(v)/sizeof((v)[0])) ^

  trustlist.c:101:22: note:
  in expansion of macro 'DIM' if (strlen (p) == DIM(item->keyid) - 1)

Which is a real standard way to use DIM, here the right hand side is
equivalent to sizeof but nevertheless it is correct.  Yes sir, we know
C.

The format string warnings I have seen were assuming that the time
structure returns valued out of scope - but if the system is that
broken, the s_n_printf catches this.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/cJSON.c b/src/cJSON.c
index 9e53012e..64a54c72 100644
--- a/src/cJSON.c
+++ b/src/cJSON.c
@@ -352,12 +352,15 @@ parse_string (cJSON * item, const char *str, const char **ep)
 		case 4:
 		  *--ptr2 = ((uc | 0x80) & 0xBF);
 		  uc >>= 6;
+                  /*FALLTHRU*/
 		case 3:
 		  *--ptr2 = ((uc | 0x80) & 0xBF);
 		  uc >>= 6;
+                  /*FALLTHRU*/
 		case 2:
 		  *--ptr2 = ((uc | 0x80) & 0xBF);
 		  uc >>= 6;
+                  /*FALLTHRU*/
 		case 1:
 		  *--ptr2 = (uc | firstByteMark[len]);
 		}