Replace our hard-coded defaults for `/MD` and `/MDd` with a first-class
abstraction to select the runtime library from an enumeration of logical
names.  We've long hesitated to do this because the idea of "runtime
library selection" touches on related concepts on several platforms.
Avoid that scope creep by simply defining an abstraction that applies
only when targeting the MSVC ABI on Windows.

Removing the old default flags requires a policy because existing
projects may rely on string processing to edit them and choose a runtime
library under the old behavior.  Add policy CMP0091 to provide
compatibility.

Fixes: #19108

The Gentoo case added by commit 1673923c (FindBoost: Add support for
Boost 1.67 with Python version suffixes, 2018-03-18, v3.11.0~3^2) left
out the `.` version component separator and instead duplicated the RPM
case.  Add the missing `.` now.

Fixes: #18743

Fixes: #18998

The QtAutogen/ManySources test generates a number of source, header, .ui and
.qrc files that get AUTOMOC, AUTOUIC and AUTORCC processed.  This stresses the
concurrency framework in `cmQtAutoMocUic` and should reveal any issues
with that.

-- add new tests for custom commands
-- minor test cleanup

Fixes #15995
Fixes #18909
Fixes #15902

-- Restructure projects and files to support proper building of targets
   Build order is determined by hierarchy of project files and folders
   Custom targets may have been run multiple times in the original file / folder structure
-- Default to build targets that are part of ALL target
-- List all known targets for this project
   Includes global targets for ALL_BUILD and INSTALL
-- Compute build order for building targets

Fixes: #19161

Also support installing headers on an INTERFACE library.
Signed-off-by: Avraham Shukron <avraham.shukron@gmail.com>
Fixes: #15234

For `MACOSX_BUNDLE` targets we generate an `Info.plist` automatically
and add it to the sources presented to Xcode.  Avoid mutating the
original target's list of sources to achieve this.  Otherwise when we
generate the same target again (e.g. in a sub-project's Xcode file) it
will look different than the first time and possibly break invariants.

Fixes: #19114

These capabilities complement MR !3190
and is also needed to solve issue #18771.

Build the GAT project with the same generator as the rest of the test.
This was accidentally left out of commit 8c8731b4 (Autogen: Add test
for CMAKE_GLOBAL_AUTOGEN/RCC_TARGET, 2018-11-11, v3.14.0-rc1~396^2~2).

The test project does not compile any sources and so does not
need to enable any languages.

The `-S` and `-B` command-line option tests do generate build systems
and so should use the generator being tested.

Previously compilers that only supported the meta-level flags
would not have any of the granular features listed. Now we
presume that they have full support and enable all the features.

Update granular feature tests to skip the actual compilation
checks for the presumed features.

The genex part of the test verifies that `$<COMPILE_FEATURES:...>`
evaluates as expected.  It does not need to actually try using code with
the associated features, as that is tested separately.

In some cases GCC reports *relative* implicit include directories.  They
are computed adaptively with respect to the current working directory
such that the effective implicit include directory is an unchanging
absolute path.  Teach our implicit include directory extraction to
recognize such paths and normalize them.

Fixes: #19133

This new capability is required to solve efficiently issue #18771

Fixes: #19097

When a dependency was already found, find_dependency did not search it
again. While this works in basic case, it does not when there are
components as the check does not take components into account.

Given the fact that there is no documentation about this optimization and
that the correct implementation is not trivial as it would require
changes in find_package to have the list of components already found we
always search dependencies.

Fix #17583.

The implicit include directory extraction added by commit 5990ecb7
(Compute implicit include directories from compiler output, 2018-12-07,
v3.14.0-rc1~108^2) leaves paths like `/usr/lib/../include` unchanged.
Fix the logic to canonicalize such paths (e.g. to `/usr/include`)
as we do for implicit link directories already.  This is important
to ensure the set of implicit directories is represented in the same
form as the include directories that will be compared to them.

Issue: #19095

Build KWSys with `CP_UTF8` internal encoding so that we can dynamically
load modules by absolute paths that contain international characters.
This is needed now that KWSys DynamicLoader uses KWSys Encoding instead
of hard-coding `CP_UTF8` itself.

Fixes #18327

Our documented standard for find module variable names is to match the
case of the find module package name.  This was overlooked when the
module was added by commit 84e7920b (FindFontconfig: Add module to
find Fontconfig, 2018-09-27, v3.14.0-rc1~523^2).

The module was released with the upper case names in CMake 3.14.0, so
fix it to have camel case names in 3.14.1.  This is incompatible but
anyone using a given release series should be using the latest patch on
it and we've made breaking fixups on newly released features like this
before.
Reported-by: Christophe Giboudeaux <christophe@krop.fr>
Fixes: #19094

Any `include_directories()` calls in toolchain files are used during our
ABI detection step even though it does not include any system headers.
Since commit 5990ecb7 (Compute implicit include directories from
compiler output, 2018-12-07, v3.14.0-rc1~108^2), that check is also used
to detect implicit include directories.  Any `include_directories()` in
a toolchain file are detected as implicit and later excluded from
explicit specification on compiler command lines, thus breaking the
purpose of the calls in the first place.

Fix the implicit include directory detection step to avoid using paths
from `include_directories()` calls in the toolchain file.

Fixes: #19079