[Bug fortran/85750] New: Default initialization of derived type array missing

["stephan.kramer at imperial dot ac.uk" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85750

            Bug ID: 85750
           Summary: Default initialization of derived type array missing
           Product: gcc
           Version: 8.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: stephan.kramer at imperial dot ac.uk
  Target Milestone: ---

In The following program, the derived type array that is returned by make_list
does not have its components initialized.

module bar
  implicit none
  type ilist
    integer :: count = 0
    integer, dimension(:), pointer :: ptr => null()
  end type ilist

  contains

  function make_list(i)
    integer, intent(in) :: i
    type(ilist), dimension(2) :: make_list

    make_list(i)%count = 1

  end function make_list

end module bar
program foo
  use bar
  implicit none

  type(ilist), dimension(:), allocatable :: mylist

  allocate(mylist(1:2))
  mylist = make_list(1)
  print *, mylist%count
  mylist = make_list(2)
  print *, mylist%count

end program foo

What I get:

$ gfortran test.f90 
$ ./a.out 
           1           0
           1           1

What I expect:
           1           0
           0           1
i.e. make_list should return an array for which all entries have a zero %count
component, except for the specified entry that's set to 1.

The program does work correctly if I leave out the %ptr from the ilist derived
type definition.

Latest gfortran I've tried is 8.1, but I see the same failure on 7.3, 7.2 and
6.2. The results are correct with gfortran 5.4

$ gfortran -v test.f90 
Driving: gfortran -v test.f90 -l gfortran -l m -shared-libgcc
Using built-in specs.
COLLECT_GCC=gfortran
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/8/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 8.1.0-1'
--with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --with-as=/usr/bin/x86_64-linux-gnu-as
--with-ld=/usr/bin/x86_64-linux-gnu-ld --program-suffix=-8
--program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie
--with-system-zlib --with-target-system-zlib --enable-objc-gc=auto
--enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-offload-targets=nvptx-none --without-cuda-driver
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 8.1.0 (Debian 8.1.0-1) 
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 /usr/lib/gcc/x86_64-linux-gnu/8/f951 test.f90 -quiet -dumpbase test.f90
-mtune=generic -march=x86-64 -auxbase test -version -fintrinsic-modules-path
/usr/lib/gcc/x86_64-linux-gnu/8/finclude -o /tmp/cch78iQf.s
GNU Fortran (Debian 8.1.0-1) version 8.1.0 (x86_64-linux-gnu)
        compiled by GNU C version 8.1.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.19-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU Fortran2008 (Debian 8.1.0-1) version 8.1.0 (x86_64-linux-gnu)
        compiled by GNU C version 8.1.0, GMP version 6.1.2, MPFR version 4.0.1,
MPC version 1.1.0, isl version isl-0.19-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 /usr/bin/x86_64-linux-gnu-as -v --64 -o /tmp/ccwUDNGB.o /tmp/cch78iQf.s
GNU assembler version 2.30 (x86_64-linux-gnu) using BFD version (GNU Binutils
for Debian) 2.30
Reading specs from /usr/lib/gcc/x86_64-linux-gnu/8/libgfortran.spec
rename spec lib to liborig
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/8/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/8/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 /usr/lib/gcc/x86_64-linux-gnu/8/collect2 -plugin
/usr/lib/gcc/x86_64-linux-gnu/8/liblto_plugin.so
-plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/8/lto-wrapper
-plugin-opt=-fresolution=/tmp/cczgT9xX.res -plugin-opt=-pass-through=-lgcc_s
-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lquadmath
-plugin-opt=-pass-through=-lm -plugin-opt=-pass-through=-lgcc_s
-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lc
-plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc --sysroot=/
--build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu -dynamic-linker
/lib64/ld-linux-x86-64.so.2 -pie
/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu/Scrt1.o
/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu/crti.o
/usr/lib/gcc/x86_64-linux-gnu/8/crtbeginS.o -L/usr/lib/gcc/x86_64-linux-gnu/8
-L/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu
-L/usr/lib/gcc/x86_64-linux-gnu/8/../../../../lib -L/lib/x86_64-linux-gnu
-L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib
-L/usr/lib/gcc/x86_64-linux-gnu/8/../../.. /tmp/ccwUDNGB.o -lgfortran -lm
-lgcc_s -lgcc -lquadmath -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc
/usr/lib/gcc/x86_64-linux-gnu/8/crtendS.o
/usr/lib/gcc/x86_64-linux-gnu/8/../../../x86_64-linux-gnu/crtn.o
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'