Commit f57b861 adds an assertion on the fact that at least one of the projections of the 2 normals at a ridge point onto the normal at triangle is positive. This assertion fails on the attached mesh (where .txtextension has to be replaced by .mesh one) with commit 4883d1a and following command line :

mmg3d_debug -v 5 -noswap -nomove temp-with-ridges.mesh

temp-with-ridges.txt