https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78356
Bug ID: 78356
Summary: segfault allocating polymorphic variable with
polymorphic component with allocatable component
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: abensonca at gmail dot com
Target Milestone: ---
The following code causes a segfault at runtime using gfortran 7.0.0 (r242406),
but runs successfully when compiled with gfortran 6.0.0. Output and output from
valgrind are appended below.
module m
implicit none
type ac
end type ac
type, extends(ac) :: a
integer, allocatable, dimension(:) :: b
end type a
type n
class(ac), allocatable, dimension(:) :: acr
contains
procedure :: ncp => nncp
end type n
contains
subroutine nncp(self,tg)
implicit none
class(n), intent(in ) :: self
class(n), intent(inout) :: tg
allocate(tg%acr(1),source=self%acr(1))
return
end subroutine nncp
end module m
program p
use m
implicit none
type(n) :: s,t
allocate(a :: s%acr(1))
call s%ncp(t)
end program
$ gfortran -v
Using built-in specs.
COLLECT_GCC=gfortran
COLLECT_LTO_WRAPPER=/home/abenson/Galacticus/Tools/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --prefix=/home/abenson/Galacticus/Tools
--enable-languages=c,c++,fortran --disable-multilib
Thread model: posix
gcc version 7.0.0 20161115 (experimental) (GCC)
$ a.out
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
Backtrace for this error:
#0 0x7ff186f0d1ef in ???
at
/data001/abenson/Galacticus/Tools/glibc-2.12.1/signal/../sysdeps/unix/sysv/linux/x86_64/sigaction.c:0
#1 0x7ff186f5a460 in ???
at ../sysdeps/x86_64/memcpy.S:161
#2 0x40167b in __copy_m_A
at /home/abenson/Galacticus/v0.9.4/c.F90:22
#3 0x400f59 in __m_MOD_nncp
at /home/abenson/Galacticus/v0.9.4/c.F90:18
#4 0x401593 in p
at /home/abenson/Galacticus/v0.9.4/c.F90:27
#5 0x4016c4 in main
at /home/abenson/Galacticus/v0.9.4/c.F90:23
Segmentation fault
$ valgrind a.out
==1544== Memcheck, a memory error detector
==1544== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==1544== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==1544== Command: a.out
==1544==
==1544== Argument 'size' of function malloc has a fishy (possibly negative)
value: -274793986988
==1544== at 0x4A05B60: malloc (vg_replace_malloc.c:299)
==1544== by 0x401647: __copy_m_A.3590 (c.F90:22)
==1544== by 0x400F59: __m_MOD_nncp (c.F90:18)
==1544== by 0x401593: MAIN__ (c.F90:27)
==1544== by 0x4016C4: main (c.F90:23)
==1544==
==1544== Source and destination overlap in memcpy(0x0, 0x2,
18446743798915564628)
==1544== at 0x4A0A4D3: memcpy (vg_replace_strmem.c:1019)
==1544== by 0x40167B: __copy_m_A.3590 (c.F90:22)
==1544== by 0x400F59: __m_MOD_nncp (c.F90:18)
==1544== by 0x401593: MAIN__ (c.F90:27)
==1544== by 0x4016C4: main (c.F90:23)
==1544==
==1544== Invalid read of size 2
==1544== at 0x4A0A6E8: memcpy (vg_replace_strmem.c:1019)
==1544== by 0x40167B: __copy_m_A.3590 (c.F90:22)
==1544== by 0x400F59: __m_MOD_nncp (c.F90:18)
==1544== by 0x401593: MAIN__ (c.F90:27)
==1544== by 0x4016C4: main (c.F90:23)
==1544== Address 0x2 is not stack'd, malloc'd or (recently) free'd
==1544==
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
Backtrace for this error:
#0 0x56431ef in ???
at
/data001/abenson/Galacticus/Tools/glibc-2.12.1/signal/../sysdeps/unix/sysv/linux/x86_64/sigaction.c:0
#1 0x4a0a6e8 in _vgr20180ZZ_libcZdsoZa_memcpy
at ../shared/vg_replace_strmem.c:1019
#2 0x40167b in ???
#3 0x400f59 in ???
#4 0x401593 in ???
#5 0x4016c4 in ???
#6 0x562fd0c in __libc_start_main
at /data001/abenson/Galacticus/Tools/glibc-2.12.1/csu/libc-start.c:226
#7 0x400728 in ???
==1544==
==1544== Process terminating with default action of signal 11 (SIGSEGV)
==1544== at 0x564313E: raise (raise.c:67)
==1544== by 0x56431EF: ??? (in
/home/abenson/Galacticus/Tools/lib/libc-2.12.1.so)
==1544== by 0x4A0A6E7: memcpy (vg_replace_strmem.c:1019)
==1544== by 0x40167B: __copy_m_A.3590 (c.F90:22)
==1544== by 0x400F59: __m_MOD_nncp (c.F90:18)
==1544== by 0x401593: MAIN__ (c.F90:27)
==1544== by 0x4016C4: main (c.F90:23)
==1544==
==1544== HEAP SUMMARY:
==1544== in use at exit: 3,964 bytes in 17 blocks
==1544== total heap usage: 21 allocs, 4 frees, 12,104 bytes allocated
==1544==
==1544== LEAK SUMMARY:
==1544== definitely lost: 0 bytes in 0 blocks
==1544== indirectly lost: 0 bytes in 0 blocks
==1544== possibly lost: 0 bytes in 0 blocks
==1544== still reachable: 3,964 bytes in 17 blocks
==1544== suppressed: 0 bytes in 0 blocks
==1544== Rerun with --leak-check=full to see details of leaked memory
==1544==
==1544== For counts of detected and suppressed errors, rerun with: -v
==1544== ERROR SUMMARY: 3 errors from 3 contexts (suppressed: 3 from 3)
Segmentation fault
Allocating the "b" component of "s%acr(1)" doesn't resolve the problem.
