diff --git a/libbacktrace/ChangeLog b/libbacktrace/ChangeLog
index 52154f01e82..c60f714aa20 100644
--- a/libbacktrace/ChangeLog
+++ b/libbacktrace/ChangeLog
@@ -1,3 +1,7 @@
+2017-07-28  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
+
+	* fileline.c (fileline_initialize): Print pid_t as long.
+
 2017-07-26  Tony Reix  <tony.reix@atos.net>
 
 	* configure.ac: Check for XCOFF32/XCOFF64.  Check for loadquery.
diff --git a/libbacktrace/fileline.c b/libbacktrace/fileline.c
index 303e4dce83a..68120583d7b 100644
--- a/libbacktrace/fileline.c
+++ b/libbacktrace/fileline.c
@@ -102,7 +102,8 @@ fileline_initialize (struct backtrace_state *state,
 	  filename = "/proc/curproc/file";
 	  break;
 	case 4:
-	  snprintf (buf, sizeof (buf), "/proc/%d/object/a.out", getpid ());
+	  snprintf (buf, sizeof (buf), "/proc/%ld/object/a.out",
+		    (long) getpid ());
 	  filename = buf;
 	  break;
 	default: