2 files changed, 3 insertions, 1 deletions
diff --git a/Changes b/Changes
index 19699b1fc..e673d5e71 100644
--- a/Changes
+++ b/Changes
@@ -96,6 +96,7 @@ Bug fixes:
 - PR#5327: (Windows) Unix.select blocks if same socket listed in first and
   third arguments
 - PR#5343: ocaml -rectypes is unsound wrt module subtyping (was still unsound)
+- PR#5350: missing return code checks in the runtime system
 - PR#5468: ocamlbuild should preserve order of parametric tags
 - PR#5547: Enable the "-use-ocamlfind" option by default
 - PR#5551: Avoid repeated lookups for missing cmi files
diff --git a/byterun/startup.c b/byterun/startup.c
index 11b18db69..923723f8d 100644
--- a/byterun/startup.c
+++ b/byterun/startup.c
@@ -88,7 +88,8 @@ static void fixup_endianness_trailer(uint32 * p)
 
 static int read_trailer(int fd, struct exec_trailer *trail)
 {
-  lseek(fd, (long) -TRAILER_SIZE, SEEK_END);
+  if (lseek(fd, (long) -TRAILER_SIZE, SEEK_END) == -1)
+    return BAD_BYTECODE;
   if (read(fd, (char *) trail, TRAILER_SIZE) < TRAILER_SIZE)
     return BAD_BYTECODE;
   fixup_endianness_trailer(&trail->num_sections);