% COMMAND-LINE: --incremental

x, y: BOOLEAN;

ASSERT (x OR y);
% EXPECT: sat
CHECKSAT;
PUSH;
ASSERT (NOT x);
% EXPECT: sat
CHECKSAT;
POP;
PUSH;
ASSERT (NOT y);
% EXPECT: sat
CHECKSAT;
POP;
% EXPECT: sat
CHECKSAT;