Created attachment 177565 [details]
Fixes segfault in bmake. Possibly sketchy.

Turns out that I can trivially segfault make with this input:

	(FOO)=val

This happens because in /usr/src/contrib/bmake/parse.c:1862 or
so, we start off with:

	for (depth = 0, cp = line + 1; depth > 0 || *cp != '='; cp++) {

which skips over the opening '(', meaning that when we see the closing ')',
the depth becomes negative, and we never break out of the loop, eventually
reading outside of mapped memory.

Starting off with 'cp = line', as in the attached patch, seems to work,
although I'm a bit suspicious about it breaking some subtle case when
parsing variables.

Still, I tested by:

	cd /usr/src/usr.bin/bmake; make; make install
	cd /usr/src/lib/libc; make clean; make
	
Seems to work. 'make world' is running now.