Re: [chrony-dev] 008-ntpera test failure

[Vincent Blut <vincent.debian@xxxxxxx>]

Hi,

Le 2022-01-11 10:07, Miroslav Lichvar a écrit :
> On Mon, Jan 10, 2022 at 03:34:28PM +0100, Vincent Blut wrote:
> > SUMMARY:
> >   TOTAL  1
> >   PASSED 0
> >   FAILED 1    (008-ntpera) (24505)
> >   SKIPPED 0   ()
> > 
> > Do you have any tips on how to properly debug this?
> 
> On what arch is the test running and what CFLAGS/CPPFLAGS are used for
> the build?
> 
> How is NTP_ERA_SPLIT set in the generated config.h file?
> 
> You could compare the bash debug output with a 64-bit system where it
> works. My first guess would be wrong calculation of the *START_DATE
> variable.
> 
> $ bash -x ./008-ntpera |& grep -o START_DATE=.*
> START_DATE=2085977996
> START_DATE=2085977996
> START_DATE=0
> START_DATE=0
> START_DATE=4294957296
> START_DATE=4294957296
> START_DATE=-10000
> START_DATE=-10000
> START_DATE=4294967296
> START_DATE=4294967296
> START_DATE=0
> START_DATE=0
> START_DATE=4294957296
> START_DATE=4294957296
> START_DATE=-10000
> START_DATE=-10000
> START_DATE=4294967296
> START_DATE=4294967296
 
I finally had some time to work on this. Your comment about the possible wrong
calculation of the CLKNETSIM_START_DATE variable reminded me that Debian's
default awk interpreter, mawk, prints long integers in scientific notation which
led me to the root cause of the 008-ntpera test failure. The attached patch
fixes that while ensuring that using GNU Awk does not cause regressions.

The following awk invocation would also lead to the same result:
awk "BEGIN {OFMT=\"%.0f\"; print $ntp_start + $start_offset}")

> -- 
> Miroslav Lichvar

Cheers,
Vincent

From 6875cff420e3e48e1cce708f3e84e300c68c2e3b Mon Sep 17 00:00:00 2001
From: Vincent Blut <vincent.debian@xxxxxxx>
Date: Wed, 12 Jan 2022 18:08:34 +0100
Subject: [PATCH] test: ensure awk commands in 008-ntpera return an integer

Some awk interpreters (e.g. mawk) print long integers in exponential
notation skewing the test result.
---
 test/simulation/008-ntpera | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/simulation/008-ntpera b/test/simulation/008-ntpera
index 2a4f332..2eea63b 100755
--- a/test/simulation/008-ntpera
+++ b/test/simulation/008-ntpera
@@ -29,7 +29,7 @@ echo "$ntp_start" | grep -q '-' && test_skip
 
 for time_offset in -1e-1 1e-1; do
 	for start_offset in 0 "2^32 - $limit"; do
-		export CLKNETSIM_START_DATE=$(awk "BEGIN {print $ntp_start + $start_offset}")
+		export CLKNETSIM_START_DATE=$(awk "BEGIN {printf \"%.0f\", $ntp_start + $start_offset}")
 		run_test || test_fail
 		check_chronyd_exit || test_fail
 		check_source_selection || test_fail
@@ -38,7 +38,7 @@ for time_offset in -1e-1 1e-1; do
 	done
 
 	for start_offset in -$limit "2^32"; do
-		export CLKNETSIM_START_DATE=$(awk "BEGIN {print $ntp_start + $start_offset}")
+		export CLKNETSIM_START_DATE=$(awk "BEGIN {printf \"%.0f\", $ntp_start + $start_offset}")
 		run_test || test_fail
 		check_chronyd_exit || test_fail
 		check_source_selection || test_fail
-- 
2.34.1

Attachment: signature.asc
Description: PGP signature