http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51529
Bug #: 51529 Summary: gfortran.dg/class_to_type_1.f03 is miscompiled: Uninitialized variable used Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: bur...@gcc.gnu.org CC: pa...@gcc.gnu.org $ gfortran -g gfortran.dg/class_to_type_1.f03 $ MALLOC_PERTURB_= ./a.out $ MALLOC_PERTURB_=33 ./a.out A fatal error occurred! Backtrace for this error: ... #6 0x400929 in __copy_MAIN___T2 at class_to_type_1.f03:5 #7 0x4013D1 in MAIN__ at class_to_type_1.f03:17 That's a typical sign for code which requires that "malloc" returns '\0'-set memory, i.e. gfortran generates code which uses an uninitialized variable.