https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66575
Bug ID: 66575 Summary: Endless compilation on missing end interface Product: gcc Version: 5.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran Assignee: unassigned at gcc dot gnu.org Reporter: gerhard.steinmetz.fort...@t-online.de Target Milestone: --- If the first "end interface" is missing : $ cat zlcti_1.f90 module m interface operator (.f.) procedure f !end interface interface operator (.g.) procedure g end interface contains integer function f(x) integer, intent(in) :: x f = x end function integer function g(x) integer, intent(in) :: x g = x end function end or wrong for whatever reason, e.g. : $ cat zlcti_2.f90 module m interface operator (.f.) procedure f end !interface interface operator (.g.) procedure g end interface contains integer function f(x) integer, intent(in) :: x f = x end function integer function g(x) integer, intent(in) :: x g = x end function end then compilation will not end, even after minutes. $ time gfortran -c zlcti_1.f90 # ^C after a few minutes real 5m10.508s user 0m0.000s sys 0m0.001s Tested with gfortran 5.1.1, 4.9.0, 4.8.3 (on SUSE Linux 13.2, 64 bit). Tested with several combinations of options and several flags.