HDF5 Fortran library documentation includes the following:

Regarding Fortran environments:


The HDF5 Fortran library requires a Fortran 2003 environment in HDF5-1.10. If the Fortran compiler being used is Fortran 2003 compliant and the installed HDF5 library was configured with the --enable-fortran option, then the resulting HDF5 Fortran library will include the Fortran 2003 environment.


Both Fortran 90 and Fortran 2003 environments are available. A small number of features are available only in Fortran 2003 environments, but most are available in both. The --enable-fortran2003 flag must be specifically included in addition to the--enable-fortran option, in order to provide a Fortran 2003 environment. Without this option, the resulting HDF5 Fortran library uses a Fortran 90 environment.


Regarding the HDF5 C/Fortran Reference Manual:

Throughout the reference manual, each Fortran subroutine description is presented alongside the corresponding C function description.