1.14 Redefines ssize_t on Windows WSL w/ Conda-Forge (GCC) Compilers

[ax3l]

Describe the bug
We have developers developing our C++ code on Windows WSL (Ubuntu) using the Conda-Forge compilers (GCC 13.3).

We noticed an error in H5public.H, where HDF5 declares a public typedef on a type named ssize_t, which breaks compiles (because it is default in the C++ standard lib, too).
ECP-WarpX/impactx#799

https://github.com/HDFGroup/hdf5/blob/hdf5_1.14.4.3/src/H5public.h#L267-L290

Expected behavior
Should not add a public define.

Platform (please complete the following information)

• HDF5 version: seen with 1.14.4, but I googled and found while googlind that others had the same issue also with 1.14.0
• OS and version: Windows 11, WSL with Ubuntu, Conda-Forge Compilers (G++/GCC)
• Compiler: G++/GCC 13.3
• Build system: autotools (HDF5 recipe on conda-forge), downstream I then use CMake for my app
• Any configure options you specified: no MPI
• MPI library and version (parallel HDF5): serial

Additional context
The code in question is a DOE SciDAC-5 supported accelerator modeling code, ImpactX. The same problem would also show in other SciDAC-5 codes that use this, e.g., WarpX, Synergia.

ECP-WarpX/impactx#799

[ax3l]

This is how conda-forge builds HDF5 for Linux/macOS (which is the package we use in WSL):
https://github.com/conda-forge/hdf5-feedstock/blob/main/recipe/build.sh