2022.06.05 13:56 "Re: [Tiff] Upgrade of CI image", by Bob Friesenhahn

However, often those prerequisite versions are determined by the platforms which require support, so they aren't typically specified in isolation from the platform support.

So we could say we'll support GCC7, but that might stem from saying we'll support NetBSD 8. The tool requirements have to come from somewhere.

We could have a policy of supporting the last n major versions of GCC or MSVC. Though GCC has changed its versioning policy recently.

I agree that this can get excessive. I would therefore say that the oldest reasonable system anad the newest are both good to have and the ones in the middle are likely skippable.

It would be wrong to say that the libtiff project 'supports' particular compiler versions and OS distributions/versions because that implies that others are not 'supported' and thus might be abnormally likely to fail. The libtiff license effectively says that there is no support at all. Libtiff is staffed by volunteers.

Libtiff now absolutely requires a C99 compiler and run-time library. It is able to compile and run under Microsoft Windows and POSIX-compliant OSs.

Ubuntu is a popular Linux distribution, but there are others which are very popular. There are plenty of other non-Linux POSIX-compliant OSs which will work just fine.

Most issues encountered are with newer verions of compilers due to introducing new warnings/optimizations and are not related to the underlying OS.

Introducing Ubuntu 22.04 LTS as a test environment seems quite valuable to me due to updated compilation environments and a much newer GNU C library. Continuing testing on Ubuntu 20.04 or 18.04 does not seem very valuable to me since failures there are unlikely. It is more useful to test on non-Linux OSs than older vintages of Linux-based OSs.

We are more likely to encounter issues due to CMake on older OS versions than we are with the compiler/headers/libraries.

Bob

Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/
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