Module Name: src
Committed By: rillig
Date: Sat Aug 19 08:19:25 UTC 2023
Modified Files:
src/usr.bin/make/unit-tests: varmod-gmtime.mk varmod-mtime.mk
Log Message:
tests/make: document bug in ':gmtime' with '%s'
To generate a diff of this commit:
cvs rdiff -u -r1.15 -r1.16 src/usr.bin/make/unit-tests/varmod-gmtime.mk
cvs rdiff -u -r1.4 -r1.5 src/usr.bin/make/unit-tests/varmod-mtime.mk
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/unit-tests/varmod-gmtime.mk
diff -u src/usr.bin/make/unit-tests/varmod-gmtime.mk:1.15 src/usr.bin/make/unit-tests/varmod-gmtime.mk:1.16
--- src/usr.bin/make/unit-tests/varmod-gmtime.mk:1.15 Thu Jun 1 20:56:35 2023
+++ src/usr.bin/make/unit-tests/varmod-gmtime.mk Sat Aug 19 08:19:25 2023
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-gmtime.mk,v 1.15 2023/06/01 20:56:35 rillig Exp $
+# $NetBSD: varmod-gmtime.mk,v 1.16 2023/08/19 08:19:25 rillig Exp $
#
# Tests for the :gmtime variable modifier, which formats a timestamp
# using strftime(3) in UTC.
@@ -145,4 +145,54 @@
. error
.endif
+
+# As of 2023-08-19, ':gmtime' but not ':localtime' reports wrong values for
+# '%s', depending on the operating system and the timezone, as demonstrated by
+# the following test program:
+#
+# for mod in gmtime localtime; do
+# for tz in UTC Europe/Berlin America/Los_Angeles; do
+# TZ=$tz bmake -r -v "\${%F %T %z %s $mod $tz:L:$mod}"
+# done
+# done
+#
+# Cygwin:
+# 2023-08-19 07:34:06 +0000 1692430446 gmtime UTC
+# 2023-08-19 07:34:06 +0000 1692430446 gmtime Europe/Berlin
+# 2023-08-19 07:34:06 +0000 1692430446 gmtime America/Los_Angeles
+# 2023-08-19 07:34:06 +0000 1692430446 localtime UTC
+# 2023-08-19 09:34:07 +0200 1692430447 localtime Europe/Berlin
+# 2023-08-19 00:34:07 -0700 1692430447 localtime America/Los_Angeles
+#
+# Looks good:
+# * ':gmtime' consistently reports timezone offset '+0000'.
+# * '%s' is independent of the timezone.
+#
+# NetBSD 10.99:
+# 2023-08-19 07:34:37 +0000 1692430477 gmtime UTC
+# 2023-08-19 07:34:37 +0100 1692426877 gmtime Europe/Berlin
+# 2023-08-19 07:34:37 -0800 1692459277 gmtime America/Los_Angeles
+# 2023-08-19 07:34:37 +0000 1692430477 localtime UTC
+# 2023-08-19 09:34:37 +0200 1692430477 localtime Europe/Berlin
+# 2023-08-19 00:34:37 -0700 1692430477 localtime America/Los_Angeles
+#
+# Looks bad:
+# * ':gmtime' reports different timezone offsets.
+# * ':gmtime' reports different seconds since the Epoch.
+# * ':gmtime' reports the timezone offset '+0100' for Europe/Berlin,
+# even though at 2023-08-19, DST with offset '+0200' was in place.
+#
+# Debian:
+# 2023-08-19 07:29:10 +0000 1692430150 gmtime UTC
+# 2023-08-19 07:29:10 +0000 1692426550 gmtime Europe/Berlin
+# 2023-08-19 07:29:10 +0000 1692458950 gmtime America/Los_Angeles
+# 2023-08-19 07:29:10 +0000 1692430150 localtime UTC
+# 2023-08-19 09:29:10 +0200 1692430150 localtime Europe/Berlin
+# 2023-08-19 00:29:10 -0700 1692430150 localtime America/Los_Angeles
+#
+# Looks mixed:
+# * ':gmtime' reports the correct timezone offset '+0000'.
+# * ':gmtime' reports different seconds since the Epoch, and the '%s'
+# value cannot be derived from the '%F %T %z' values.
+
all:
Index: src/usr.bin/make/unit-tests/varmod-mtime.mk
diff -u src/usr.bin/make/unit-tests/varmod-mtime.mk:1.4 src/usr.bin/make/unit-tests/varmod-mtime.mk:1.5
--- src/usr.bin/make/unit-tests/varmod-mtime.mk:1.4 Sat Aug 19 01:34:21 2023
+++ src/usr.bin/make/unit-tests/varmod-mtime.mk Sat Aug 19 08:19:25 2023
@@ -1,11 +1,11 @@
-# $NetBSD: varmod-mtime.mk,v 1.4 2023/08/19 01:34:21 sjg Exp $
+# $NetBSD: varmod-mtime.mk,v 1.5 2023/08/19 08:19:25 rillig Exp $
#
# Tests for the ':mtime' variable modifier, which maps each word of the
# expression to that file's modification time.
# Note: strftime() uses mktime() for %s and mktime() assumes localtime
# so this should match time()
-start:= ${%s:L:localtime}
+start:= ${%s:L:localtime} # see varmod-gmtime.mk, keyword '%s'
# Ensure that this makefile exists and has a modification time. If the file
