Even though this variable gets set to CMAKE_<LANG>_COMPILER-NOTFOUND when
the compiler is not found, CMake<LANG>Compiler.cmake gets removed by
cmGlobalGenerator::EnableLanguage so in try compiles the value is empty.
Quote references to the variable in

 Modules/CMake(C|CXX|Fortran)Information.cmake
 Modules/CMakeDetermineCompilerId.cmake

to avoid dropping arguments from commands that expect them.

If no CMAKE_${lang}_COMPILER is available then do not try to run
it to determine the compiler vendor.

2d0287dd cmRST: Process literal blocks after paragraphs ending in '::'
7b9ae406 cmRST: Do not process inline markup in code-block literals

a80fe4b1 use size_t for GeneratorExpressionContent::ContentLength to fix some warnings

4e184a21 string: Add CONCAT sub-command

e5ec8ad4 Xcode: Generate 'folder' source type for directories (#14498)

b9fe4b63 VS: Document VS_GLOBAL_KEYWORD and VS_KEYWORD relationship (#14493)

f063c455 Consider targets with double colons to be IMPORTED or ALIAS targets.

0698714c VS: Set .NET target framework version for VS 7-9 (#14499)

bcd5de77 cmake: Always pass through stdout/stderr in --build mode

a8226e91 cmake: Drop support for "-i" wizard mode

Teach cmRST to recognize non-markup lines ending in '::' followed by a
blank line as starting a literal block.  Record the whole block as if it
were a literal block directive and print it just like a code block.
Extend the CMakeLib.testRST test to cover such cases.

Move the ProcessDirectiveParsedLiteral and ProcessDirectiveCodeBlock
method internals into an OutputMarkupLines helper.  Pass through it a
new "inlineMarkup" parameter and teach OutputLine to understand it.
When false, do not process inline markup.  Extend the CMakeLib.testRST
test to cover the two cases.

CMake/Source/cmGeneratorExpressionParser.cxx: In member function ‘void cmGeneratorExpressionParser::ParseGeneratorExpression(std::vector<cmGeneratorExpressionEvaluator*>&)’:
CMake/Source/cmGeneratorExpressionParser.cxx:116:55: warning: conversion to ‘unsigned int’ from ‘long int’ may alter its value [-Wconversion]
CMake/Source/cmGeneratorExpressionParser.cxx:240:39: warning: conversion to ‘int’ from ‘long int’ may alter its value [-Wconversion]

Add a string(CONCAT) command to simply concatenate input arguments
together.  This will be useful for combining strings from different
quoting syntaxes.  Add a RunCMake.string test covering these cases.

Teach the Xcode generator to set 'lastKnownFileType' to be 'folder' for
file references that are directories.  If you set 'explicitFileType' to
'sourcecode', then Xcode cannot browse the directory.

These two target properties serve the same purpose for different versions
of Visual Studio.  Document the versions covered by each property.

Reported-by: mar.na@t-online.de

Introduce a policy to control the behavior.

The AliasTargets unit test already tests that using a
double-semicolon in the name is not an error. Change the ExportImport
test to use a namespace with a double-semicolon too.

b04f3b9a Create make rules for INTERFACE_LIBRARY targets.
dba4962b Makefile: Always create clean target command

The result is that the depends of the target are created.

So,

 add_library(somelib foo.cpp)
 add_library(anotherlib EXCLUDE_FROM_ALL foo.cpp)
 add_library(extra EXCLUDE_FROM_ALL foo.cpp)
 target_link_libraries(anotherlib extra)

 add_library(iface INTERFACE)
 target_link_libraries(iface INTERFACE anotherlib)

Executing 'make iface' will result in the anotherlib and extra targets
being made.

Adding a regular executable to the INTERFACE of an INTERFACE_LIBRARY
will not result in the executable being built with 'make iface' because
of the logic in cmComputeTargetDepends::AddTargetDepend.

So far, this is implemented only for the Makefile generator. Other
generators will follow if this feature is possible for them.

Make INTERFACE_LIBRARY targets part of the all target by default.
Test this by building the all target and making the expected library
EXCLUDE_FROM_ALL.

Teach the VS 7-9 generators to honor the

 VS_DOTNET_TARGET_FRAMEWORK_VERSION

target property.  This was already done for VS >= 10 by commit cfe6300a
(VS: Add support for .NET target framework version, 2013-06-14).

Inspired-by: mar.na@t-online.de

187385a8 cmCoreTryCompile: Fix typo in comments.
af2a3ab6 cmTarget: Remove unused variable.
620b0e92 target_link_libraries(): Fix code snippet in documentation.
2d4ce805 cmPolicies: Fix typo
d6dd2646 include(): Use lower case and () to refer to the include() command.

765d7839 cmSystemTools: Drop old RunCommand method
52b80b26 exec_program: Re-implement using KWSys Process
c076476d cmake: Drop "cmake -E comspec" Win9x helper
f5511352 cmExtraEclipseCDT4Generator: Replace RunCommand with RunSingleCommand

6d50d019 Help: Add introduction section to cmake-policies manual

216afc8a MSVC: Add /FS flag for cl >= 18 to allow parallel compilation (#14492)

daa0f6f9 Add Lua-style long brackets and long comments to CMake language
a8c65234 cmListFileLexer: Convert CRLF -> LF newlines explicitly
dbd93336 cmListFileLexer: Allow a leading UTF-8 Byte-Order-Mark (#11137)
56457837 cmListFileLexer: Allow command names with one letter (#14181)

abfebefb Cygwin: Avoid legacy warnings in RunCMake.CMP0026 test

1b7117a8 VS 6: Do not try Intel Fortran .vfproj file with msdev

Add 'S' to match actual variable names.

All calls to this method have been replaced by newer infrastructure.
Remove it and the supporting cmWin32ProcessExecution class.

Drop use of cmSystemTools::RunCommand.  It used popen on UNIX
(equivalent to /bin/sh -c "$command") and direct CreateProcess calls on
Windows.  Implement equivalent behavior using the KWSys Process library.
Copy windows shortpath conversion logic from cmSystemTools::RunCommand.

Since we dropped Win9x support there is no need for this helper.

Set the minimum required version of CMake high enough to avoid the
warning for CMAKE_LEGACY_CYGWIN_WIN32.  The warning appears on stderr
and breaks the expected output matching.

Teach CMakeDetermineCompilerId to skip trying to build a .vfproj
file for Intel Fortran under Visual Studio 6.  The msdev command-line
build produces a popup error dialog that hangs the configuration.

Avoid use of the old cmSystemTools::RunCommand by using RunSingleCommand
instead.

Explain the concept behind policies.