Add CLANG_BUILD_TOOLS as a clang counterpart for LLVM_BUILD_TOOLS

LLVM_BUILD_TOOLS is a boolean variable that controls whether or not generated
targets for llvm tools are built by the "all" target. CLANG_BUILD_TOOLS is an
analogous variable for clang targets.

This is useful functionality for selectively disabling the building of clang
targets by default to speed up builds.

In terms of implementation, I just followed the model of LLVM's implementation
of this functionality.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275006 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -342,6 +342,9 @@ endif()
 
 add_definitions( -D_GNU_SOURCE )
 
+option(CLANG_BUILD_TOOLS
+  "Build the Clang tools. If OFF, just generate build targets." ON)
+
 option(CLANG_ENABLE_ARCMT "Build ARCMT." ON)
 if (CLANG_ENABLE_ARCMT)
   set(ENABLE_CLANG_ARCMT "1")

cmake/modules/AddClang.cmake

@@ -121,17 +121,24 @@ macro(add_clang_executable name)
 endmacro(add_clang_executable)
 
 macro(add_clang_tool name)
+  if (NOT CLANG_BUILD_TOOLS)
+    set(EXCLUDE_FROM_ALL ON)
+  endif()
+
   add_clang_executable(${name} ${ARGN})
-  install(TARGETS ${name}
-    RUNTIME DESTINATION bin
-    COMPONENT ${name})
-
-  if(NOT CMAKE_CONFIGURATION_TYPES)
-    add_custom_target(install-${name}
-      DEPENDS ${name}
-      COMMAND "${CMAKE_COMMAND}"
-              -DCMAKE_INSTALL_COMPONENT=${name}
-              -P "${CMAKE_BINARY_DIR}/cmake_install.cmake")
+
+  if (CLANG_BUILD_TOOLS)
+    install(TARGETS ${name}
+      RUNTIME DESTINATION bin
+      COMPONENT ${name})
+
+    if(NOT CMAKE_CONFIGURATION_TYPES)
+      add_custom_target(install-${name}
+        DEPENDS ${name}
+        COMMAND "${CMAKE_COMMAND}"
+        -DCMAKE_INSTALL_COMPONENT=${name}
+        -P "${CMAKE_BINARY_DIR}/cmake_install.cmake")
+    endif()
   endif()
 endmacro()