In file included from /home/whitequark/Projects/boolector/deps/install/include/minisat/core/Solver.h:29:
/home/whitequark/Projects/boolector/deps/install/include/minisat/core/SolverTypes.h:55:16: error: friend declaration of ‘Minisat::Lit mkLit(Minisat::Var, bool)’ specifies default arguments and isn’t a definition [-fpermissive]
   55 |     friend Lit mkLit(Var var, bool sign = false);
      |                ^~~~~
/home/whitequark/Projects/boolector/deps/install/include/minisat/core/SolverTypes.h:63:14: error: friend declaration of ‘Minisat::Lit Minisat::mkLit(Var, bool)’ specifies default arguments and isn’t the only declaration [-fpermissive]
   63 | inline  Lit  mkLit     (Var var, bool sign) { Lit p; p.x = var + var + (int)sign; return p; }
      |              ^~~~~
/home/whitequark/Projects/boolector/deps/install/include/minisat/core/SolverTypes.h:55:16: note: previous declaration of ‘Minisat::Lit Minisat::mkLit(Var, bool)’
   55 |     friend Lit mkLit(Var var, bool sign = false);
      |                ^~~~~