In brief: A namelist read of a structure component that is a vector when that structure has another component that is a structure results in a runtime error. 

Test file:

  program test

  implicit none

  type tao_title_struct
    character(2) justify   
  end type

  type tao_plot_page_struct
    real shape_height_max 
    type (tao_title_struct) title ! Comment this line out and the bug goes away.
    real size(2)
  end type

  type (tao_plot_page_struct) plot_page

  namelist / params / plot_page

  open (1, file = 'test.in')
  read (1, nml = params)
  close (1)

  end program

The file test.in is:

  &params
    plot_page%size = 1, 2
  /


Compiling and running gives:

[atf2code@lnx209 test]$ gfortran -v -save-temps test.f90
Driving: gfortran -v -save-temps test.f90 -lgfortranbegin -lgfortran -lm -shared-libgcc
Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: ../gcc-4.4.1/configure --prefix=/home/atf2code/atf2/usr_local --with-gmp=/home/atf2code/atf2/usr_local --with-mpfr=/home/atf2code/atf2/usr_local
Thread model: posix
gcc version 4.4.1 (GCC) 
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-shared-libgcc' '-mtune=generic'
 /a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../libexec/gcc/i686-pc-linux-gnu/4.4.1/f951 test.f90 -quiet -dumpbase test.f90 -mtune=generic -auxbase test -version -fintrinsic-modules-path /a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/finclude -o test.s
GNU Fortran (GCC) version 4.4.1 (i686-pc-linux-gnu)
        compiled by GNU C version 4.4.1, GMP version 4.3.1, MPFR version 2.4.1.
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-shared-libgcc' '-mtune=generic'
 as -V -Qy -o test.o test.s
GNU assembler version 2.15.92.0.2 (i386-redhat-linux) using BFD version 2.15.92.0.2 20040927
COMPILER_PATH=/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../libexec/gcc/i686-pc-linux-gnu/4.4.1/:/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../libexec/gcc/
LIBRARY_PATH=/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/:/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/:/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-shared-libgcc' '-mtune=generic'
 /a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../libexec/gcc/i686-pc-linux-gnu/4.4.1/collect2 --eh-frame-hdr -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o /a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/crtbegin.o -L/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1 -L/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc -L/a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/../../.. test.o -lgfortranbegin -lgfortran -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc /a/lnx113/nfs/acc/temp/atf2/usr_local/bin/../lib/gcc/i686-pc-linux-gnu/4.4.1/crtend.o /usr/lib/crtn.o

[atf2code@lnx209 test]$ ./a.out 
At line 20 of file test.f90 (unit = 1, file = 'test.in')
Fortran runtime error: Cannot match namelist object name 1


Note: If the "title" component of tao_plot_page_struct is commented out or moved below the "size" component then the program runs without fail.