Description of problem:
make v. 3.82 was broken somehow and incorrectly parses environment variables.

As I know 3.81 was OK.
Also, we built 4.1 from sources and it is also OK.

Version-Release number of selected component (if applicable):
3.82

How reproducible:
always

Steps to Reproduce:
	1. create Makefile:
```
test: TEST ?= true
test:
        echo "TEST=$(TEST)"
```

2. check make version
$ make -v
GNU Make 3.82
Built for x86_64-redhat-linux-gnu
Copyright (C) 2010 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.
go@devtools-1-002.shared.stg.las1:~

3. run make
$ make test TEST=false
echo "TEST=f�"
TEST=f�

Actual results:
echo "TEST=f�"
TEST=f�


Expected results:
echo "TEST=false"
TEST=false


Additional info: