The following Makefile illustrates the issue:

$ cat >Makefile <<EOF
all:
echo "abc" | grep "b"
.PHONY: all
$ make all # works as expected
$ make all > /dev/null
grep: (standard input): Invalid argument
make: *** [Makefile:2: all] Error 2

The bug was introduced by commit 4fa6f48b573267e758650e114ec158d97916411e
(introducing the usage of splice), which was first released in grep version
2.27.

My environment:

$ make --version
GNU Make 4.2.1
Built for x86_64-pc-linux-gnu
Copyright (C) 1988-2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

$ grep --version
grep (GNU grep) 2.27
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Mike Haertel and others, see <
http://git.sv.gnu.org/cgit/grep.git/tree/AUTHORS>.


Patch attached.

--
Benno Fünfstück