The following code is legal, but segfaults at runtime when compiled with gfortran:
$ cat a.f90 character(len=10) :: s s = "abcdefghij" s(6:5) = s(7:5) print *, s end $ ifort a.f90 -check all && ./a.out abcdefghij $ gfortran a.f90 && ./a.out zsh: segmentation fault ./a.out -- Summary: assignments to and from zero-sized string selections not handled Product: gcc Version: 4.2.0 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: fortran AssignedTo: fxcoudert at gcc dot gnu dot org ReportedBy: fxcoudert at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27958