2020.12.26 20:57 "Re: [Tiff] Wrong information about request and avalability of external codecs", by Bob Friesenhahn

The CMake logic is a direct copy of the Autoconf configure.ac logic. I think in this case we could improve it a bit. The root cause of the problems is that we only check for a library if specifically requested. For example:

The only settings which really matter for Autoconf are 'enable' (AC_ARG_ENABLE) and 'with' (AC_ARG_WITH) as known to Autoconf. For example 'enable_zlib' is a true Autoconf flag option, and --with-zlib-include-dir is a completely unneccessary convenience option which does not turn anything on or off.

Finding the component does depend on the compiler finding the headers and libraries, which may require some user assistance.

Bob

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