krb5 commit: Add null check to placate static analysis tools

https://github.com/krb5/krb5/commit/a1a9e428b4971c2c8a5520e6c5f28deef3f94228
commit a1a9e428b4971c2c8a5520e6c5f28deef3f94228
Author: Martin Kittel <[email protected]>
Date:   Wed Mar 29 09:22:18 2017 +0200

    Add null check to placate static analysis tools
    
    In trace_format() when processing lenstr, if p is NULL and len is 0,
    skip the call to buf_add_printable_len() as Coverity considers it an
    unconditional dereference of p.
    
    [[email protected]: added explanation to commit message]

 src/lib/krb5/os/trace.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/lib/krb5/os/trace.c b/src/lib/krb5/os/trace.c
index 83c8d4d..1f9be80 100644
--- a/src/lib/krb5/os/trace.c
+++ b/src/lib/krb5/os/trace.c
@@ -173,7 +173,7 @@ trace_format(krb5_context context, const char *fmt, va_list ap)
             p = va_arg(ap, const char *);
             if (p == NULL && len != 0)
                 k5_buf_add(&buf, "(null)");
-            else
+            else if (p != NULL)
                 buf_add_printable_len(&buf, p, len);
         } else if (strcmp(tmpbuf, "hexlenstr") == 0) {
             len = va_arg(ap, size_t);