Add guards for grib_is_missing_string

src/grib_accessor_class_bufr_data_element.c

@@ -603,7 +603,7 @@ static int get_native_type(grib_accessor* a)
 {
     grib_accessor_bufr_data_element* self = (grib_accessor_bufr_data_element*)a;
     int ret                               = GRIB_TYPE_DOUBLE;
-
+    DebugAssert(self);
     switch (self->type) {
         case BUFR_DESCRIPTOR_TYPE_STRING:
             ret = GRIB_TYPE_STRING;

src/grib_parse_utils.c

@@ -314,6 +314,7 @@ int grib_accessors_list_print(grib_handle* h, grib_accessors_list* al, const cha
     char long_format[]       = "%ld";   /* default format for printing integer keys */
     char default_separator[] = " ";
     grib_accessor* a         = al->accessor;
+    DebugAssert(a);
 
     /* Number of columns specified as 0 means print on ONE line i.e. num cols = infinity */
     if (maxcols == 0)

src/grib_value.c

@@ -599,7 +599,9 @@ int grib_is_missing_string(grib_accessor* a, unsigned char* x, size_t len)
         }
     }
 
-    ret = (a == NULL || ((a->flags & GRIB_ACCESSOR_FLAG_CAN_BE_MISSING) && ret == 1)) ? 1 : 0;
+    if (!a) return ret;
+
+    ret = ( ((a->flags & GRIB_ACCESSOR_FLAG_CAN_BE_MISSING) && ret == 1) ) ? 1 : 0;
     return ret;
 }