Remove static initializers introduced by open-vcdiff's logging.h.

sdch/sdch.gyp

Index: sdch/sdch.gyp
diff --git a/sdch/sdch.gyp b/sdch/sdch.gyp
index d84be582ed7f9dba0b326e61b428ecd4ed3e0b8b..7601e99c338fe678077669d47e3237a94eaeaee9 100644
--- a/sdch/sdch.gyp
+++ b/sdch/sdch.gyp
@@ -14,6 +14,7 @@
         '../third_party/zlib/zlib.gyp:zlib',
       ],
       'sources': [
+        'logging_forward.h',
         'open-vcdiff/src/addrcache.cc',
         'open-vcdiff/src/blockhash.cc',
         'open-vcdiff/src/blockhash.h',
@@ -31,8 +32,6 @@
         'open-vcdiff/src/headerparser.h',
         'open-vcdiff/src/instruction_map.cc',
         'open-vcdiff/src/instruction_map.h',
-        'open-vcdiff/src/logging.cc',
-        'open-vcdiff/src/logging.h',

[wtc, 2013/11/12 02:17:39]

Please confirm that you don't want to remove these two files from the source
tree.

Why don't we just replace open-vcdiff/src/logging.h with the contents of
logging_forward.h?

[wtc, 2013/11/12 02:19:30]

Please ignore this question. I found the answer in the CL's description.

         'open-vcdiff/src/rolling_hash.h',
         'open-vcdiff/src/testing.h',
         'open-vcdiff/src/varint_bigendian.cc',
@@ -46,6 +45,7 @@
       ],
       'include_dirs': [
         'open-vcdiff/src',
+        '..',

[wtc, 2013/11/12 02:17:39]

Is this pointing to the src/sdch directory? Why isn't this '.'?

[Nico, 2013/11/12 03:34:10]

It's pointing to src/, so that the include of "base/logging.h" succeeds.

[wtc, 2013/11/12 18:14:03]

Thank you. This was not obvious to me, so it might be worth a comment.

Also, should this be done by adding a dependency on '../base/base.gyp:base'
instead? base/base.gyp:base has this:

      'direct_dependent_settings': {
        'include_dirs': [
          '..',
        ],
      },

[Nico, 2013/11/12 18:34:42]

Makes sense, done.

       ],
       'direct_dependent_settings': {
         'include_dirs': [
@@ -59,6 +59,37 @@
         [ 'OS == "mac"', { 'include_dirs': [ 'mac' ] } ],
         [ 'OS == "win"', { 'include_dirs': [ 'open-vcdiff/vsprojects' ] } ],
       ],
+      # open-vcdiff's logging.h introduces static initializers. This was
+      # reported upstream years ago (
+      # https://code.google.com/p/open-vcdiff/issues/detail?id=33 ). Since
+      # upstream won't fix this, work around it on the chromium side: Define
+      # the header guard so that open-vcdiff's logging.h doesn't get used, and
+      # inject a header that forwards to base/logging.h instead (which doesn't
+      # introduce static initializers).
+      'defines': [
+        'OPEN_VCDIFF_LOGGING_H_',

[wtc, 2013/11/12 02:17:39]

Why don't we define this macro in logging_forward.h?

[Nico, 2013/11/12 03:34:10]

That works too. I put it here so that it's next to the comment that adds the
forced include. If you prefer, I can move it into the .h file (there's a comment
like this too after all).

…actually, since you asked, you probably do prefer that, so done :-)

+      ],
+      'variables': {
+        'logging_path': 'logging_forward.h',
+        'conditions': [
+          # gyp leaves unspecified what the cwd is when running the compiler,
+          # and gyp/linux doesn't have a built-in way for forcing an include.
+          # So hardcode the base directory. If this spreads, provide native
+          # support in gyp, like we have for gyp/mac and gyp/windows.
+          # path.
+          ['"<(GENERATOR)"=="ninja"', { 'logging_dir': '../..' },
+                                      { 'logging_dir': '.' }
+          ],
+        ],
+      },
+      # GCC_PREFIX_HEADER is relative to the current directory,
+      # ForcedIncludeFiles is relative to include_dirs, cflags relative to the
+      # build directory.
+      'xcode_settings': { 'GCC_PREFIX_HEADER': '<(logging_path)' },
+      'msvs_settings': {
+        'VCCLCompilerTool': { 'ForcedIncludeFiles': [ 'sdch/<(logging_path)' ] }
+      },
+      'cflags': [ '-include', '<(logging_dir)/sdch/<(logging_path)' ],
     },
   ],
 }