ICE on valid code. Might be related to PR 18769. Taken from PR 29471 comment 5.
real(kind(0d0)) :: NaN = transfer(ishft(int(z'FFF80000',8),32),0d0) print *, NaN end gives: foo.f90:1: internal compiler error: in gfc_conv_constant, at fortran/trans-const.c:348 -- Summary: NaN transfer - internal compiler error: in gfc_conv_constant Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31194