Include definition for MSVC ssize_t

[BickfordA]

Adding the definition for ssize_t would allow for compiling with MSVC c11/c17.

[jmarshall]

See the previous discussion in #1025.

[jkbonfield]

Our main work is on Unix/MacOS, and Windows support so far has been using Unix-derived compilers, such as the MinGW tool chain. We just don't have the capacity in group to fully support all the nuances of another platform.

However, if it really is just 1 or 2 very minor things, then perhaps we can add definitions which aid compilation. However it's not something we're likely to be doing in a continuous integration service (unless you wish to contribute magic to make that work too) so it's always potentially going to break again.

Can you confirm how many other problems there are when compiling with MSVC? Ie when doing a "make -k" to let it continue beyond errors, how many types of error are there?

[BickfordA]

Thanks for looking at this! This and the static array initialization reference in: #1374 were the only changes i needed. Everything else could be handled with #defines and some options in the config.h.

I also saw this ticket which looks like maybe some forward movement in this direction: #1377

Happy to help if I can! I could also could put the block behind a flag so that it could be turned on/off if people don't want the behavior.

I currently am using CMake to drive the compilation (so some files are not being built tests, plugins etc) but i could look at using nmake and getting the out put of the compilation if that would be helpful.

[jkbonfield]

Closing as replaced by #1377 (now merged).