Recently we taught find_package that the NO_MODULE option is implied
when it is recursively invoked in a find-module. This behavior may be
confusing because two identical calls may enter different modes
depending on context. It also disallows the possibility that one
find-module defers to another find-module by changing CMAKE_MODULE_PATH
and recursively invoking find_package. This change reverts the feature.
Package version test files may now declare that they are unsuitable for
use with the project testing them. This is important when the version
being tested does not provide a compatible ABI with the project target
environment.
These changes teach find_package to behave nicely when invoked
recursively inside a find-module for the same package. The module will
never be recursively loaded again. Version arguments are automatically
forwarded.
Provide VERSION_LESS, VERSION_EQUAL, and VERSION_GREATER operators in
the if() command. This simplifies component-wise comparison of version
numbers in the form "major[.minor[.patch[.tweak]]]".
Make the number of version components specified explicitly available.
Set variables for unspecified version components to "0" instead of
leaving them unset. This simplifies version number handling for find-
and config-modules. Also support a fourth "tweak" version component
since some packages use them.
- Added EXACT option to request an exact version.
- Enforce version using check provided by package.
- Updated FindPackageTest to test versioning in config mode.
CMAKE_FIND_PREFIX_PATH is both an environment variable and a cmake variable,
which is a list of base directories where FIND_PATH, FIND_FILE, FIND_PROGRAM
and FIND_LIBRARY will search in the respective subdirectories
Alex