build/solaris/Makefile contains the following line that tries to
find the root of the workspace (or the file system):

    # Unless GAMMADIR is set on the command line, search upward from
    # the current directory for a parent directory containing "src/share/vm".
    # If that fails, look for $GAMMADIR in the environment.
    # When the tree of subdirs is built, this setting is stored in each flags.make.
    GAMMADIR := $(shell until ([ -d dev ]&&echo $${GAMMADIR:-/GAMMADIR/}) || ([ -d src/share/vm ]&&pwd); do cd ..; done)

which works fine as long as it finds a "src/share/vm" subdirectory,
or backs up into a directory with a "dev" subdirectory. If we need
that clause and we aren't in a filesystem with /dev at the root, we
will loop forever, which seems to be what that clause is trying to
prevent.

This might be a problem, for example, if someone chroot'ed us into
the directory where they wanted to do the build.