modeflbuilder: do not crash if a mclassdef cannot be created

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/modelbuilder.nit b/src/modelbuilder.nit
index 556e767..cb657ac 100644 (file)
--- a/src/modelbuilder.nit
+++ b/src/modelbuilder.nit
@@ -592,6 +592,10 @@ class ModelBuilder
                        self.build_a_mclassdef(nmodule, nclassdef)
                end
 
+               for nclassdef in nmodule.n_classdefs do
+                       if nclassdef.mclassdef == null then return # forward error
+               end
+
                # Create inheritance on all classdefs
                for nclassdef in nmodule.n_classdefs do
                        self.build_a_mclassdef_inheritance(nmodule, nclassdef)