On a glibc system, I'm seeing 2 test failures in automake 1.16.3:
$ ./configure --prefix=/arch/x86_64-linux-gnu/gnu-inst-automake/1.16.3
$ make
$ make check
...
FAIL: t/vala-headers.sh
...
FAIL: t/vala-mix2.sh
...

Find attached the log files (redacted for privacy reasons).

vala and valac exist in /usr/bin.

Bruno