Bugfix for steady;

1.) Fixes cases where model was not truly linear, but Dynare did not catch mistake because fvec and jacob contained cancelling NaN
2.) Use correct error code 22 if NaN appear instead of generic 20

matlab/evaluate_steady_state.m

@@ -72,7 +72,16 @@ function [ys,params,info] = evaluate_steady_state(ys_init,M,options,oo,steadysta
             fh_static = str2func([M.fname '_static']);
             [fvec,jacob] = fh_static(ys_init,exo_ss, ...
                                      params);
-            if max(abs(fvec)) > 1e-12
+
+            ii = find(~isfinite(fvec));
+            if ~isempty(ii)
+                ys=fvec;
+                check=1;
+                disp(['STEADY:  numerical initial values or parameters incompatible with the following' ...
+                      ' equations'])
+                disp(ii')
+                disp('Check whether your model in truly linear')
+            elseif isempty(ii) && max(abs(fvec)) > 1e-12
                 ys = ys_init-jacob\fvec;
             else
                 ys = ys_init;
@@ -94,6 +103,9 @@ function [ys,params,info] = evaluate_steady_state(ys_init,M,options,oo,steadysta
             resid = evaluate_static_model(ys_init,exo_ss,params,M,options);
         end
         info(2) = resid'*resid ;
+        if isnan(info(2))
+            info(1)=22;
+        end
         return
     end