Merge topic 'ExternalProject_exclude-from-all'

1ddcc582 ExternalProject: Add EXCLUDE_FROM_ALL option to ExternalProject_Add
0a1c0129 ExternalProject: Add EXCLUDE_FROM_MAIN option to ExternalProject_Add_Step

1 files changed, 19 insertions, 5 deletions

diff --git a/Modules/ExternalProject.cmake b/Modules/ExternalProject.cmake
index e490e69..0f651e9 100644
--- a/Modules/ExternalProject.cmake
+++ b/Modules/ExternalProject.cmake
@@ -16,6 +16,7 @@
 #    [LIST_SEPARATOR sep]        # Sep to be replaced by ; in cmd lines
 #    [TMP_DIR dir]               # Directory to store temporary files
 #    [STAMP_DIR dir]             # Directory to store step timestamps
+#    [EXCLUDE_FROM_ALL 1]        # The "all" target does not depend on this
 #   #--Download step--------------
 #    [DOWNLOAD_NAME fname]       # File name to store (if not end of URL)
 #    [DOWNLOAD_DIR dir]          # Directory to store downloaded files
@@ -119,6 +120,7 @@
 #    [DEPENDERS steps...]    # Steps that depend on this step
 #    [DEPENDS files...]      # Files on which this step depends
 #    [ALWAYS 1]              # No stamp file, step always runs
+#    [EXCLUDE_FROM_MAIN 1]   # Main target does not depend on this step
 #    [WORKING_DIRECTORY dir] # Working directory for command
 #    [LOG 1]                 # Wrap step in script to log output
 #    )
@@ -1192,14 +1194,17 @@ function(ExternalProject_Add_Step name step)
   set(complete_stamp_file "${cmf_dir}${cfgdir}/${name}-complete")
   _ep_get_step_stampfile(${name} ${step} stamp_file)
 
-  add_custom_command(APPEND
-    OUTPUT ${complete_stamp_file}
-    DEPENDS ${stamp_file}
-    )
-
   _ep_parse_arguments(ExternalProject_Add_Step
                       ${name} _EP_${step}_ "${ARGN}")
 
+  get_property(exclude_from_main TARGET ${name} PROPERTY _EP_${step}_EXCLUDE_FROM_MAIN)
+  if(NOT exclude_from_main)
+    add_custom_command(APPEND
+      OUTPUT ${complete_stamp_file}
+      DEPENDS ${stamp_file}
+      )
+  endif()
+
   # Steps depending on this step.
   get_property(dependers TARGET ${name} PROPERTY _EP_${step}_DEPENDERS)
   foreach(depender IN LISTS dependers)
@@ -1909,6 +1914,9 @@ function(ExternalProject_Add name)
   set(cmf_dir ${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles)
   set(complete_stamp_file "${cmf_dir}${cfgdir}/${name}-complete")
 
+  # The "ALL" option to add_custom_target just tells it to not set the
+  # EXCLUDE_FROM_ALL target property. Later, if the EXCLUDE_FROM_ALL
+  # argument was passed, we explicitly set it for the target.
   add_custom_target(${name} ALL DEPENDS ${complete_stamp_file})
   set_property(TARGET ${name} PROPERTY _EP_IS_EXTERNAL_PROJECT 1)
   _ep_parse_arguments(ExternalProject_Add ${name} _EP_ "${ARGN}")
@@ -1916,6 +1924,12 @@ function(ExternalProject_Add name)
   _ep_get_step_stampfile(${name} "done" done_stamp_file)
   _ep_get_step_stampfile(${name} "install" install_stamp_file)
 
+  # Set the EXCLUDE_FROM_ALL target property if required.
+  get_property(exclude_from_all TARGET ${name} PROPERTY _EP_EXCLUDE_FROM_ALL)
+  if(exclude_from_all)
+    set_property(TARGET ${name} PROPERTY EXCLUDE_FROM_ALL TRUE)
+  endif()
+
   # The 'complete' step depends on all other steps and creates a
   # 'done' mark.  A dependent external project's 'configure' step
   # depends on the 'done' mark so that it rebuilds when this project