autoconf-2.70 increases make check failure of automake on Solaris x86/x64

Hello,
Installed autoconf-2.70, and found it increases make check failure of automake.

$ uname -a
SunOS hidden 5.11 11.3 i86pc i386 i86pc

$ gcc --version
gcc (GCC) 10.2.0


$ autoconf --version
autoconf (GNU Autoconf) 2.70

In automake-1.16.3 directory,
$ ./configure CC=gcc
$ make
$ make check

Following failures are detected.
FAIL: t/deprecated-acinit.sh
FAIL: t/distcheck-missing-m4.sh
FAIL: t/distcheck-outdated-m4.sh
FAIL: t/init.sh
FAIL: t/lex-clean-cxx.sh
FAIL: t/lex-depend-cxx.sh
FAIL: t/libobj-basic.sh
FAIL: t/remake-not-after-make-dist.sh

On the other hand, only 2 failure with autoconf-2.69.
PASS: t/deprecated-acinit.sh
PASS: t/distcheck-missing-m4.sh
PASS: t/distcheck-outdated-m4.sh
PASS: t/init.sh
FAIL: t/lex-clean-cxx.sh
FAIL: t/lex-depend-cxx.sh
PASS: t/libobj-basic.sh
PASS: t/remake-not-after-make-dist.sh


Regards,