Since commit 8b2dab9bd if you try to build MongoDB with wiredTiger disabled (scons option --wiredtiger=off) the scons crashes with following stack trace:
AttributeError: 'list' object has no attribute 'startswith': File "/home/user/mongodb/mongo/SConstruct", line 3150: variant_dir='$BUILD_DIR', File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 541: return _SConscript(self.fs, *files, **subst_kw) File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 250: exec _file_ in call_stack[-1].globals File "/home/user/mongodb/mongo/src/SConscript", line 24: env.SConscript('mongo/SConscript', exports=['env']) File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 541: return _SConscript(self.fs, *files, **subst_kw) File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 250: exec _file_ in call_stack[-1].globals File "/home/user/mongodb/mongo/src/mongo/SConscript", line 44: 'env', File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 541: return _SConscript(self.fs, *files, **subst_kw) File "/usr/local/lib/scons-2.5.1/SCons/Script/SConscript.py", line 250: exec _file_ in call_stack[-1].globals File "/home/user/mongodb/mongo/src/mongo/db/SConscript", line 866: "views/views_mongod", File "/usr/local/lib/scons-2.5.1/SCons/Environment.py", line 260: return MethodWrapper.__call__(self, target, source, *args, **kw) File "/usr/local/lib/scons-2.5.1/SCons/Environment.py", line 224: return self.method(*nargs, **kwargs) File "/usr/local/lib/scons-2.5.1/SCons/Builder.py", line 626: return self._execute(env, target, source, OverrideWarner(kw), ekw) File "/usr/local/lib/scons-2.5.1/SCons/Builder.py", line 547: tlist, slist = self._create_nodes(env, target, source) File "/usr/local/lib/scons-2.5.1/SCons/Builder.py", line 511: target, source = self.emitter(target=tlist, source=slist, env=env) File "/usr/local/lib/scons-2.5.1/SCons/Builder.py", line 205: target, source = e(target, source, env) File "/usr/local/lib/scons-2.5.1/SCons/Builder.py", line 339: target, source = emitter(target, source, env) File "/home/user/mongodb/mongo/site_scons/libdeps.py", line 253: prereq.target_node, lib_builder.get_prefix(env), lib_builder.get_suffix(env)) File "/usr/local/lib/scons-2.5.1/SCons/Util.py", line 1063: path, fn = os.path.split(os.path.normpath(fname)) File "/usr/lib/python2.7/posixpath.py", line 335: initial_slashes = path.startswith('/')