tests/testsuite.at was using the undocumented internal shell variable
$as_echo to set its own variable $ECHO. M4sh stopped setting this
variable in a patch committed to autoconf development trunk in January
of 2013, which was mostly harmless since there was a fallback setting
for $ECHO. As of March 2020, however, merely mentioning $as_echo in
an m4sh input file will trigger a -Wobsolete warning.
The fix is to promote the fallback setting to be the default setting
and not reference $as_echo anymore. This is safe for the same reason
it was safe for autoconf to stop setting $as_echo -- 'printf %s\n' is a
reliable way to do echoing in all of the shells that are worth worrying
about anymore.
---
tests/testsuite.at | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/tests/testsuite.at b/tests/testsuite.at
index d561c2a4..9e33c75a 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -29,8 +29,7 @@ m4_divert_push([PREPARE_TESTS])dnl
: ${AUTOCONF=autoconf}
: ${AUTOMAKE=automake}
: ${AUTORECONF=autoreconf}
-test set = "${ECHO+set}" || ECHO=${as_echo-'printf %s\n'}
-: ${ECHO=$as_echo}
+: ${ECHO='printf %s\n'}