Reland Don't set -fvisibility=hidden for iOS Debug in GYP.

build/common.gypi

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 5056 matching lines @@
           'CLANG_LINK_OBJC_RUNTIME': 'NO',          # -fno-objc-link-runtime
           'COPY_PHASE_STRIP': 'NO',
           'GCC_C_LANGUAGE_STANDARD': 'c99',         # -std=c99
           'GCC_CW_ASM_SYNTAX': 'NO',                # No -fasm-blocks
           'GCC_ENABLE_CPP_EXCEPTIONS': 'NO',        # -fno-exceptions
           'GCC_ENABLE_CPP_RTTI': 'NO',              # -fno-rtti
           'GCC_ENABLE_PASCAL_STRINGS': 'NO',        # No -mpascal-strings
           # GCC_INLINES_ARE_PRIVATE_EXTERN maps to -fvisibility-inlines-hidden
           'GCC_INLINES_ARE_PRIVATE_EXTERN': 'YES',
           'GCC_OBJC_CALL_CXX_CDTORS': 'YES',        # -fobjc-call-cxx-cdtors
-          'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',      # -fvisibility=hidden
           'GCC_THREADSAFE_STATICS': 'NO',           # -fno-threadsafe-statics
           'GCC_TREAT_WARNINGS_AS_ERRORS': 'YES',    # -Werror
           'GCC_VERSION': '4.2',
           'GCC_WARN_ABOUT_MISSING_NEWLINE': 'YES',  # -Wnewline-eof
           'USE_HEADERMAP': 'NO',
           'WARNING_CFLAGS': [
             '-Wall',
             '-Wextra',
             # Don't warn about unused function parameters.
             '-Wno-unused-parameter',
@@ skipping 51 matching lines @@
             ['OS=="ios" and target_subarch!="arm32" and \
               "<(GENERATOR)"=="xcode"', {
               'OTHER_CFLAGS': [
                 # TODO(ios): when building Chrome for iOS on 64-bit platform
                 # with Xcode, the -Wshorted-64-to-32 warning is automatically
                 # enabled. This cause failures when compiling protobuf code,
                 # so disable the warning. http://crbug.com/359107
                 '-Wno-shorten-64-to-32',
               ],
             }],
           ],

[sdefresne, 2016/01/07 16:50:21]

I think you should put your code here.

         },
         'conditions': [
           ['clang==1', {
             'variables': {
               'clang_dir': '../third_party/llvm-build/Release+Asserts/bin',
             },
           }],
           ['asan==1', {
             'xcode_settings': {
               'OTHER_CFLAGS': [
@@ skipping 20 matching lines @@
               ['_toolset=="target"', {
                 'cflags': [
                   '-fsanitize-coverage=<(sanitizer_coverage)',
                 ],
                 'defines': [
                   'SANITIZER_COVERAGE',
                 ],
               }],
             ],
           }],
+          ['OS=="mac"', {
+            'xcode_settings': {
+              'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',    # -fvisibility=hidden
+            },
+          }],
+          ['OS=="ios"', {
+            'configurations': {
+              'Debug': {
+                'xcode_settings': {
+                  # XCTests inject a dynamic library into the application. If
+                  # fvisibility is set to hidden, then some symbols needed by
+                  # XCTests are not available. Disable this setting for
+                  # Debug configuration.
+                  'GCC_SYMBOLS_PRIVATE_EXTERN': 'NO',
+                },
+              },
+              'Release': {
+                'xcode_settings': {
+                  'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',    # -fvisibility=hidden
+                },
+              },
+            },
+          }],
         ],
         'target_conditions': [
           ['_type!="static_library"', {
             'xcode_settings': {'OTHER_LDFLAGS': ['-Wl,-search_paths_first']},
             'conditions': [
               ['asan==1', {
                 'xcode_settings': {
                   'OTHER_LDFLAGS': [
                     '-fsanitize=address',
                   ],
@@ skipping 1195 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }