tests: Don't printf a known NULL symname in backtrace-dwarf.c.

GCC9 on 32bit systems might warn about '%s' directive argument is null
for symname in backtrace-dwarf.c. Just check whether symname is NULL.

This is an identical fix for the same issue as found in backtrace.c,
but now in backtrace-dwarf.c

Signed-off-by: Mark Wielaard <mark@klomp.org>

diff --git a/tests/ChangeLog b/tests/ChangeLog
index a4f5dd3edbacb7b76c064cc9f4b0408c4797e5d9..d6dafa467d68c3f3c42f7e11315b783a560c28d3 100644 (file)
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,8 @@
+2019-04-30  Mark Wielaard  <mark@klomp.org>
+
+       * backtrace-dwarf.c (frame_callback): Explicitly check symname is
+       NULL.
+
 2019-04-30  Mark Wielaard  <mark@klomp.org>
 
        * backtrace.c (frame_callback): Explicitly check symname is NULL.

diff --git a/tests/backtrace-dwarf.c b/tests/backtrace-dwarf.c
index dfbf1856bfa5728902a68c724d96750c5d4eeae1..f446bc3b4678a2af804155c94de53d9f3d6bab9c 100644 (file)
--- a/tests/backtrace-dwarf.c
+++ b/tests/backtrace-dwarf.c
@@ -101,7 +101,7 @@ frame_callback (Dwfl_Frame *state, void *frame_arg)
   if (mod)
     symname = dwfl_module_addrname (mod, pc_adjusted);
 
-  printf ("%#" PRIx64 "\t%s\n", (uint64_t) pc, symname);
+  printf ("%#" PRIx64 "\t%s\n", (uint64_t) pc, symname ?: "<null>");
 
   if (symname && (strcmp (symname, "main") == 0
                  || strcmp (symname, ".main") == 0))