https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77327
--- Comment #5 from Vittorio Zecca <zeccav at gmail dot com> --- The test case you propose, dec_structure_13.f90, does not trigger the asan memory checker. As I wrote before, the test case gfortran.dg/import4.f90 does trigger the asan memory checker. In your test case I do not understand the final statement "call sub2(u2)" because sub2 is not defined.