https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126292
Bug ID: 126292
Summary: abnormal compilation time
Product: gcc
Version: 16.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: mfvalin at gmail dot com
Target Milestone: ---
the following code takes an abnormally long time to compile (order 10+ minutes)
with other compilers it takes less than a quarter of a second
> gfortran --version
GNU Fortran (GCC) 16.1.0
(versions 14/15 of the compiler behave the same way)
(9.4.0 compiles at a "normal" speed)
with -DFAST the compile time with gfortran becomes "normal"
the problem looks similar to what was addressed in ID 20923
regression ?
MODULE DEMO
IMPLICIT NONE
INTEGER, PARAMETER :: JPRB = SELECTED_REAL_KIND(13,300) !< Standard real type
REAL(KIND=JPRB) :: TACOS2(0:35250)
END MODULE
SUBROUTINE BUGGED( ERR)
USE DEMO
IMPLICIT NONE
INTEGER :: ERR
INTEGER :: I
ERR = 0
#if !defined(FAST)
TACOS2 = ACOS( (/ (I, I= 64000, 99250) /) / 100000.0_JPRB)
! gfortran takes a very long time to compile the above line
#else
DO I = 64000, 99250
TACOS2(I-64000) = ACOS(REAL(I, KIND=JPRB) / 100000.0_JPRB)
ENDDO
! the above loop compiles normally
#endif
END SUBROUTINE BUGGED
