CMakeForceCompiler: De-deprecate until more use cases have alternatives

We deprecated this module in commit v3.5.0-rc1~295^2
(CMakeForceCompiler: Deprecate this module and its macros, 2015-10-19)
in order to determine whether anyone still has use cases that require
it.  Indeed we still need to provide a way to work with toolchains that
cannot link binaries without special flags.  Remove the deprecation
warnings until we can provide an alternative to the module for this use
case.

Help/release/3.5.rst

@@ -159,9 +159,6 @@ Other
 Deprecated and Removed Features
 ===============================
 
-* The :module:`CMakeForceCompiler` module and its macros are now deprecated.
-  See module documentation for an explanation.
-
 * The :manual:`cmake(1)` ``-E time`` command now properly passes arguments
   with spaces or special characters through to the child process.  This
   may break scripts that worked around the bug with their own extra

Modules/CMakeForceCompiler.cmake

@@ -2,7 +2,9 @@
 # CMakeForceCompiler
 # ------------------
 #
-# Deprecated.  Do not use.
+# Discouraged.  Avoid using this module if possible.  It will be deprecated
+# by a future version of CMake once alternatives have been provided for all
+# toolchain file use cases.
 #
 # The macros provided by this module were once intended for use by
 # cross-compiling toolchain files when CMake was not able to automatically
@@ -12,6 +14,12 @@
 # CMake detects from a compiler is now too extensive to be provided by
 # toolchain files using these macros.
 #
+# The only known remaining use case for these macros is to write toolchain
+# files for cross-compilers that cannot link binaries without special flags or
+# custom linker scripts.  These macros cause CMake to skip checks it normally
+# performs as part of enabling a language and introspecting the toolchain.
+# However, skipping these checks may limit some generation functionality.
+#
 # -------------------------------------------------------------------------
 #
 # Macro CMAKE_FORCE_C_COMPILER has the following signature:
@@ -70,8 +78,6 @@
 #  License text for the above reference.)
 
 macro(CMAKE_FORCE_C_COMPILER compiler id)
-  message(DEPRECATION "The CMAKE_FORCE_C_COMPILER macro is deprecated.  "
-    "Instead just set CMAKE_C_COMPILER and allow CMake to identify the compiler.")
   set(CMAKE_C_COMPILER "${compiler}")
   set(CMAKE_C_COMPILER_ID_RUN TRUE)
   set(CMAKE_C_COMPILER_ID ${id})
@@ -84,8 +90,6 @@ macro(CMAKE_FORCE_C_COMPILER compiler id)
 endmacro()
 
 macro(CMAKE_FORCE_CXX_COMPILER compiler id)
-  message(DEPRECATION "The CMAKE_FORCE_CXX_COMPILER macro is deprecated.  "
-    "Instead just set CMAKE_CXX_COMPILER and allow CMake to identify the compiler.")
   set(CMAKE_CXX_COMPILER "${compiler}")
   set(CMAKE_CXX_COMPILER_ID_RUN TRUE)
   set(CMAKE_CXX_COMPILER_ID ${id})
@@ -98,8 +102,6 @@ macro(CMAKE_FORCE_CXX_COMPILER compiler id)
 endmacro()
 
 macro(CMAKE_FORCE_Fortran_COMPILER compiler id)
-  message(DEPRECATION "The CMAKE_FORCE_Fortran_COMPILER macro is deprecated.  "
-    "Instead just set CMAKE_Fortran_COMPILER and allow CMake to identify the compiler.")
   set(CMAKE_Fortran_COMPILER "${compiler}")
   set(CMAKE_Fortran_COMPILER_ID_RUN TRUE)
   set(CMAKE_Fortran_COMPILER_ID ${id})