Printing allocatable v.s. normal arrays from fortran code in GDB

I am writing some scientific fortran code where I have some allocatable arrays.
When I want to print them in GDB, the data I get is gibberish, even
though the program itself easily can compute with the allocated array.
To demonstrate the problem I have created a small archive containing a
test program, a makefile and the output generated when run on my
system.
The program is alloc.f90
The output is is output.txt
The program can be compiled and run by running make on a system with
gfortran installed.
Because the mailing list doesn't support attatchments the tarfile is
available at (1 Kb)
https://www.dropbox.com/s/zj4pgcbp44p5q4z/alloc.tar.gz?dl=1

The interesting part is line 22-23 in output.txt. I would expect the
output on the two lines to be the same, but for some reason the
allocatable array is printed wrong.

Is this a known problem? Am I misunderstanding how allocatable arrays
work? Any help would be greatly appreciated.

GDB version: GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.2) 7.7.1
gfortran version: GNU Fortran (Ubuntu 4.9.2-0ubuntu1~14.04) 4.9.2

Have a nice day - Morten