https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67987
Bug ID: 67987 Summary: ICE on declaring and initializing character with negative len Product: gcc Version: 5.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran Assignee: unassigned at gcc dot gnu.org Reporter: gerhard.steinmetz.fort...@t-online.de Target Milestone: --- Declaring and initializing a character with negative len (< -1) requests memory of about 2^64 (= 18446744073709551616) : $ cat z1.f90 program p character(-8) :: c = ' ' end $ gfortran -g -O0 -Wall -fcheck=all -fno-frontend-optimize z1.f90 f951: out of memory allocating 18446744073709551588 bytes after a total of 434176 bytes --- Warning without assignment : $ cat z2.f90 program p character(-8) :: c end $ gfortran -g -O0 -Wall -fcheck=all -fno-frontend-optimize z2.f90 z2.f90:2:13: character(-8) :: c 1 Warning: CHARACTER variable at (1) has negative length -8, the length has been set to zero [-Wsurprising] --- With len = -1, reaction depends on used compiler options : $ cat z3.f90 program p character(-1) :: c = 'c' end $ gfortran -g -O0 -Wall -fcheck=all -fno-frontend-optimize z3.f90 gfortran: internal compiler error: Segmentation fault (program f951) --- Same issue with "character parameter".