https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85641
Bug ID: 85641 Summary: [7/8 Regression] ICE with string concatenate Product: gcc Version: 7.3.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran Assignee: unassigned at gcc dot gnu.org Reporter: antony at cosmologist dot info Target Milestone: --- This worked for a long time in gcc 7, I think it broke in gcc 7.3 (not exactly sure which minor version). It is also broken in gcc 8 and latest master: gfortran -c test.f90 where test.f90 is program tester character(LEN=:), allocatable :: fields integer j character(LEN=4), parameter :: CMB_CL_Fields = 'TEBP' fields = '' j=1 fields = fields // CMB_CL_Fields(j:j) end program tester