Catch by const-reference

Reported by Semmle's LGTM
(https://lgtm.com/projects/g/diffblue/cbmc/alerts/?mode=list).

Author: tautschnig

src/goto-programs/printf_formatter.cpp

@@ -47,7 +47,7 @@ void printf_formattert::print(std::ostream &out)
     while(!eol()) process_char(out);
   }
 
-  catch(eol_exceptiont)
+  catch(const eol_exceptiont &)
   {
   }
 }

src/solvers/sat/satcheck_minisat2.cpp

@@ -142,7 +142,7 @@ void satcheck_minisat2_baset<T>::lcnf(const bvt &bv)
 
     clause_counter++;
   }
-  catch(Minisat::OutOfMemoryException)
+  catch(const Minisat::OutOfMemoryException &)
   {
     messaget::error() << "SAT checker ran out of memory" << eom;
     status = statust::ERROR;
@@ -264,7 +264,7 @@ propt::resultt satcheck_minisat2_baset<T>::prop_solve()
     status=statust::UNSAT;
     return resultt::P_UNSATISFIABLE;
   }
-  catch(Minisat::OutOfMemoryException)
+  catch(const Minisat::OutOfMemoryException &)
   {
     messaget::error() <<
       "SAT checker ran out of memory" << eom;
@@ -288,7 +288,7 @@ void satcheck_minisat2_baset<T>::set_assignment(literalt a, bool value)
     value ^= sign;
     solver->model[v] = Minisat::lbool(value);
   }
-  catch(Minisat::OutOfMemoryException)
+  catch(const Minisat::OutOfMemoryException &)
   {
     messaget::error() << "SAT checker ran out of memory" << eom;
     status = statust::ERROR;
@@ -359,7 +359,7 @@ void satcheck_minisat_simplifiert::set_frozen(literalt a)
       solver->setFrozen(a.var_no(), true);
     }
   }
-  catch(Minisat::OutOfMemoryException)
+  catch(const Minisat::OutOfMemoryException &)
   {
     messaget::error() << "SAT checker ran out of memory" << eom;
     status = statust::ERROR;