Improve.

diff --git a/grading/threads/run-tests b/grading/threads/run-tests
index a08882211e8e8242f02cfdfa78af6e8edc9bc36d..7fcc91cc6853256f82712f0f5f19be62d00d8cca 100755 (executable)
--- a/grading/threads/run-tests
+++ b/grading/threads/run-tests
@@ -431,9 +431,10 @@ sub verify_common {
                $A2L = "i386-elf-addr2line";
            }
            open (A2L, "$A2L -fe output/$test/kernel.o @addrs|");
-           my ($function);
-           while ($function = <A2L>) {
-               my ($line) = <A2L>;
+           for (;;) {
+               my ($function, $line);
+               last unless $function = <A2L>;
+               $line = <A2L>;
                chomp $function;
                chomp $line;
                $details .= "  $function ($line)\n";