Re-word the documentation to make clear that CMake integrates usage
requirements during generation and not synchronously during
configuration or execution of target_link_libraries.

This establishes that linking is used to propagate usage-requirements
between targets in CMake code. The use of the target_link_libraries
command as the API for this is chosen because introducing a new command
would introduce confusion due to multiple commands which differ only in
a subtle way.

Explain in the documentation for the legacy signature

 target_link_libraries(foo bar)

that the other signatures like

 target_link_libraries(foo LINK_INTERFACE_LIBRARIES ...)
 target_link_libraries(foo LINK_PRIVATE ...)

will set the LINK_INTERFACE_LIBRARIES target property and therefore make
libraries specified only by the legacy signature private.

Don't add generator expressions to variables which are used
for CMP0003, CMP0004, and the old-style _LIB_DEPENDS content. They
will not be evaluated when read anyway and would probably confuse
the code reading them.

This makes it legitimate to use target_link_libraries with generator
expressions as arguments.

State explicitly that multiple calls append (rather than replace).

Yury G. Kudryashov authored Feb 25, 2012 and Brad King committed Feb 29, 2012

Use const_cast for the special case in cmFindBase where
GetFullDocumentation calls GenerateDocumentation.

Change "thelink" to "the link".

Stephen Kelly authored Oct 07, 2011 and Brad King committed Nov 22, 2011

Makes it possible to specify the link dependencies and link
interfaces in one command without repetition.

The target_link_libraries command requires its first argument to be a
target in the current directory.  Document this and update the error
message to be more specific.  While at it, format the error message with
a call stack.

This converts the CMake license to a pure 3-clause OSI-approved BSD
License.  We drop the previous license clause requiring modified
versions to be plainly marked.  We also update the CMake copyright to
cover the full development time range.

This documents CMake's support for cycles in the dependency graph of
STATIC libraries.

The target_link_libraries command supports flags as well as libraries.
This makes the support explicit in the documentation.

Create a DEBUG_CONFIGURATIONS global property as a way for projects to
specify which configuration names are considered to be 'debug'
configurations.

Rename the recently added INTERFACE mode of the target_link_libraries()
command to LINK_INTERFACE_LIBRARIES.  This makes it much more distinct
from a normal call to the command, and clearly states its connection to
the property of the same name.  Also require the option to appear
immediately after the target name to make it a mode rather than an
option.

Create an INTERFACE option to the target_link_libraries command to help
set the LINK_INTERFACE_LIBRARIES and LINK_INTERFACE_LIBRARIES_DEBUG
properties.  This will help users specify link interfaces using
variables from Find*.cmake modules that include the 'debug' and
'optimized' keywords.

The "debug", "optimized", and "general" link library type specifier
arguments to the target_link_library commands are sometimes repeated in
user code due to variable expansion and other complications.  Instead of
silently accepting the duplicates and trying to link to a bogus library
like "optimized.lib", warn and ignore the earlier specifiers.

STYLE: Improve documentation of target_link_libraries command to make target-level dependency explicit.  See bug #6043.

ENH: add return and break support to cmake, also change basic command invocation signature to be able to return extra informaiton via the cmExecutionStatus class

fix many bugs related to target names being computed inconsistently.

- Centralized computation of a target's file name to a method in
  cmTarget.  Now that global knowledge is always available the
  *_CMAKE_PATH cache variables are no longer needed.

- Centralized computation of link library command lines and link
  directory search order.

- Moved computation of link directories needed to link CMake targets
  to be after evaluation of linking dependencies.

This also removed alot of duplicate code in which each version had its
own bugs.

This commit is surrounded by the tags

  CMake-TargetNameCentralization1-pre

and

  CMake-TargetNameCentralization1-post

so make the large set of changes easy to identify.

ENH: Report an error when ADD_LIBRARY and TARGET_LINK_LIBRARIES are in the wrong order and fix CMakeLists files to actually work

ENH: Added reference to Copyright.txt.  Removed old reference to ITK copyright.  Changed program name to CMake instead of Insight in source file header.  Also removed tabs.

ENH: change InitialPass to take a const reference to the argument string, to avoid changes to the file cache