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From: "anlauf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/96018] Optimization issue with external HDF5 library
Date: Wed, 01 Jul 2020 12:24:43 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96018

--- Comment #3 from anlauf at gcc dot gnu.org ---
You are not using HDF5's "native" Fortran interface directly, but a
clumsy way with c_f_pointer to obscure your code.  Any reason for that?

Have you considered using RESHAPE for what you seem to try to get?

Your code will run into issues if the dummy "array" is not contiguous.

Also, I'd consider not checking a library's return code bad style.

Also, can you give details on the exact compiler version and HDF5?=