Properly separate host and target builds when using external natives.

tools/gyp/v8.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 37 matching lines @@
           # dependency however the Android toolchain requires libv8_base.a
           # to appear before libv8_snapshot.a so it's listed explicitly.
           'dependencies': ['v8_base', 'v8_snapshot'],
         }],
         ['v8_use_snapshot!="true" and v8_use_external_startup_data==0', {
           # The dependency on v8_base should come from a transitive
           # dependency however the Android toolchain requires libv8_base.a
           # to appear before libv8_snapshot.a so it's listed explicitly.
           'dependencies': ['v8_base', 'v8_nosnapshot'],
         }],
+        ['v8_use_external_startup_data==1 and want_separate_host_toolset==1', {
+          'dependencies': ['v8_base', 'v8_external_snapshot'],
+          'target_conditions': [
+            ['_toolset=="host"', {
+              'inputs': [
+                '<(PRODUCT_DIR)/snapshot_blob_host.bin',
+              ],
+            }, {
+              'inputs': [
+                '<(PRODUCT_DIR)/snapshot_blob.bin',
+              ],
+            }],
+          ],
+        }],
         ['v8_use_external_startup_data==1 and want_separate_host_toolset==0', {
           'dependencies': ['v8_base', 'v8_external_snapshot'],
-        }],
-        ['v8_use_external_startup_data==1 and want_separate_host_toolset==1', {
-          'dependencies': ['v8_base', 'v8_external_snapshot#host'],
+          'inputs': [ '<(PRODUCT_DIR)/snapshot_blob.bin', ],
         }],
         ['component=="shared_library"', {
           'type': '<(component)',
           'sources': [
             # Note: on non-Windows we still build this file so that gyp
             # has some sources to link into the component.
             '../../src/v8dll-main.cc',
           ],
           'include_dirs': [
             '../..',
@@ skipping 138 matching lines @@
             'V8_SHARED',
           ],
         }],
       ]
     },
     {
       'target_name': 'v8_external_snapshot',
       'type': 'static_library',
       'conditions': [
         ['want_separate_host_toolset==1', {
-          'toolsets': ['host'],
+          'toolsets': ['host', 'target'],
           'dependencies': [
             'mksnapshot#host',
             'js2c#host',
-            'natives_blob#host',
+            'natives_blob',
         ]}, {
           'toolsets': ['target'],
           'dependencies': [
             'mksnapshot',
             'js2c',
             'natives_blob',
           ],
         }],
         ['component=="shared_library"', {
           'defines': [
@@ skipping 17 matching lines @@
       'sources': [
         '../../src/natives-external.cc',
         '../../src/snapshot-external.cc',
       ],
       'actions': [
         {
           'action_name': 'run_mksnapshot (external)',
           'inputs': [
             '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mksnapshot<(EXECUTABLE_SUFFIX)',
           ],
-          'outputs': [
-            '<(INTERMEDIATE_DIR)/snapshot.cc',
-            '<(PRODUCT_DIR)/snapshot_blob.bin',
+          'conditions': [
+            ['want_separate_host_toolset==1', {
+              'target_conditions': [
+                ['_toolset=="host"', {
+                  'outputs': [
+                    '<(INTERMEDIATE_DIR)/snapshot.cc',
+                    '<(PRODUCT_DIR)/snapshot_blob_host.bin',

[vogelheim, 2014/08/29 14:10:55]

I'm a bit skeptical here: snapshot.cc and snapshot_blob.bin represent largely
the same data, but in a different format: One as constants in C, the other as a
blob file. So if we disambiguate between the host and target blob file, we would
probably also disambiguate the equivalent .cc file.

Admittedly this is more pattern matching than a specific problem this might
cause, but... well.

[rmcilroy, 2014/08/29 14:15:47]

I think the difference is that snapshot.cc is already disambiguated between host
/ target because it is in <(INTERMEDIATE_DIR) (which is different for host and
target), whereas <(PRODUCT_DIR) is the same for both the host / target builds
and so has to be explicitly differentiated.

[vogelheim, 2014/08/29 14:55:39]

Ah, yes, that makes sense. Thanks for the explanation!

+                  ],
+                }, {
+                  'outputs': [
+                    '<(INTERMEDIATE_DIR)/snapshot.cc',
+                    '<(PRODUCT_DIR)/snapshot_blob.bin',
+                  ],
+                }],
+              ],
+            }, {
+              'outputs': [
+                '<(INTERMEDIATE_DIR)/snapshot.cc',
+                '<(PRODUCT_DIR)/snapshot_blob.bin',
+              ],
+            }],
           ],
           'variables': {
             'mksnapshot_flags': [
               '--log-snapshot-positions',
               '--logfile', '<(INTERMEDIATE_DIR)/snapshot.log',
             ],
             'conditions': [
               ['v8_random_seed!=0', {
                 'mksnapshot_flags': ['--random-seed', '<(v8_random_seed)'],
               }],
@@ skipping 1061 matching lines @@
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
     {
       'target_name': 'natives_blob',
       'type': 'none',
       'conditions': [
         [ 'v8_use_external_startup_data==1', {
-          'dependencies': ['js2c'],
+          'conditions': [
+            ['want_separate_host_toolset==1', {
+              'dependencies': ['js2c#host'],
+            }, {
+              'dependencies': ['js2c'],
+            }],
+          ],
           'actions': [{
             'action_name': 'concatenate_natives_blob',
             'inputs': [
               '../../tools/concatenate-files.py',
               '<(SHARED_INTERMEDIATE_DIR)/libraries.bin',
               '<(SHARED_INTERMEDIATE_DIR)/libraries-experimental.bin',
             ],
-            'outputs': [
-              '<(PRODUCT_DIR)/natives_blob.bin',
+            'conditions': [
+              ['want_separate_host_toolset==1', {
+                'target_conditions': [
+                  ['_toolset=="host"', {
+                    'outputs': [
+                      '<(PRODUCT_DIR)/natives_blob_host.bin',
+                    ],
+                    'action': [
+                      'python', '<@(_inputs)', '<(PRODUCT_DIR)/natives_blob_host.bin'
+                    ],
+                  }, {
+                    'outputs': [
+                      '<(PRODUCT_DIR)/natives_blob.bin',
+                    ],
+                    'action': [
+                      'python', '<@(_inputs)', '<(PRODUCT_DIR)/natives_blob.bin'
+                    ],
+                  }],
+                ],
+              }, {
+                'outputs': [
+                  '<(PRODUCT_DIR)/natives_blob.bin',
+                ],
+                'action': [
+                  'python', '<@(_inputs)', '<(PRODUCT_DIR)/natives_blob.bin'
+                ],
+              }],
             ],
-            'action': ['python', '<@(_inputs)', '<@(_outputs)'],
           }],
         }],
         ['want_separate_host_toolset==1', {
-          'toolsets': ['host'],
+          'toolsets': ['host', 'target'],
         }, {
           'toolsets': ['target'],
         }],
       ]
     },
     {
       'target_name': 'js2c',
       'type': 'none',
       'conditions': [
         ['want_separate_host_toolset==1', {
@@ skipping 155 matching lines @@
         }],
         ['v8_compress_startup_data=="bz2"', {
           'libraries': [
             '-lbz2',
           ]
         }],
       ],
     },
   ],
 }