linux: add -fvisibility=hidden to build flags

We use this on OS X, so it shouldn't be harmful and it will fix a visibility
issue that came up in
  http://groups.google.com/group/chromium-dev/browse_thread/thread/800bda968bdc8f29

BUG=17943

Review URL: http://codereview.chromium.org/332035

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@30253 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 22 insertions, 10 deletions

diff --git a/build/common.gypi b/build/common.gypi
index b5e2279..da571a9 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -493,6 +493,7 @@
           '<(werror)',  # See note above about the werror variable.
           '-pthread',
           '-fno-exceptions',
+          '-fvisibility=hidden',
           '-Wall',
           '-D_FILE_OFFSET_BITS=64',
         ],
@@ -694,6 +695,11 @@
             'cflags': [ '-gstabs' ],
             'defines': ['USE_LINUX_BREAKPAD'],
           }],
+          ['library=="shared_library"', {
+            # When building with shared libraries, remove the visiblity-hiding
+            # flag.
+            'cflags!': [ '-fvisibility=hidden' ],
+          }],
         ],
       },
     }],
diff --git a/webkit/tools/npapi_layout_test_plugin/main.cpp b/webkit/tools/npapi_layout_test_plugin/main.cpp
index e24e203..032985f 100644
--- a/webkit/tools/npapi_layout_test_plugin/main.cpp
+++ b/webkit/tools/npapi_layout_test_plugin/main.cpp
@@ -43,6 +43,12 @@
 #define NPAPI
 #endif
 
+#if defined(__GNUC__) && __GNUC__ >= 4
+#define EXPORT __attribute__((visibility ("default")))
+#else
+#define EXPORT
+#endif
+
 #if defined(OS_LINUX)
 #include <X11/Xlib.h>
 #endif
@@ -89,22 +95,22 @@ static void log(NPP instance, const char* format, ...)
 
 // Plugin entry points
 extern "C" {
-    NPError NPAPI NP_Initialize(NPNetscapeFuncs *browserFuncs
+    EXPORT NPError NPAPI NP_Initialize(NPNetscapeFuncs *browserFuncs
 #if defined(OS_LINUX)
                                 , NPPluginFuncs *pluginFuncs
 #endif
                                 );
-    NPError NPAPI NP_GetEntryPoints(NPPluginFuncs *pluginFuncs);
-    void NPAPI NP_Shutdown(void);
+    EXPORT NPError NPAPI NP_GetEntryPoints(NPPluginFuncs *pluginFuncs);
+    EXPORT void NPAPI NP_Shutdown(void);
 
 #if defined(OS_LINUX)
-    NPError NP_GetValue(NPP instance, NPPVariable variable, void *value);
-    const char* NP_GetMIMEDescription(void);
+    EXPORT NPError NPAPI NP_GetValue(NPP instance, NPPVariable variable, void *value);
+    EXPORT const char* NPAPI NP_GetMIMEDescription(void);
 #endif
 }
 
 // Plugin entry points
-NPError NPAPI NP_Initialize(NPNetscapeFuncs *browserFuncs
+EXPORT NPError NPAPI NP_Initialize(NPNetscapeFuncs *browserFuncs
 #if defined(OS_LINUX)
                             , NPPluginFuncs *pluginFuncs
 #endif
@@ -118,7 +124,7 @@ NPError NPAPI NP_Initialize(NPNetscapeFuncs *browserFuncs
 #endif
 }
 
-NPError NPAPI NP_GetEntryPoints(NPPluginFuncs *pluginFuncs)
+EXPORT NPError NPAPI NP_GetEntryPoints(NPPluginFuncs *pluginFuncs)
 {
     pluginFuncs->version = 11;
     pluginFuncs->size = sizeof(pluginFuncs);
@@ -139,7 +145,7 @@ NPError NPAPI NP_GetEntryPoints(NPPluginFuncs *pluginFuncs)
     return NPERR_NO_ERROR;
 }
 
-void NPAPI NP_Shutdown(void)
+EXPORT void NPAPI NP_Shutdown(void)
 {
 }
 
@@ -498,12 +504,12 @@ NPError NPP_SetValue(NPP instance, NPNVariable variable, void *value)
 }
 
 #if defined(OS_LINUX)
-NPError NP_GetValue(NPP instance, NPPVariable variable, void *value)
+EXPORT NPError NPAPI NP_GetValue(NPP instance, NPPVariable variable, void *value)
 {
     return NPP_GetValue(instance, variable, value);
 }
 
-const char* NP_GetMIMEDescription(void) {
+EXPORT const char* NPAPI NP_GetMIMEDescription(void) {
     // The layout test LayoutTests/fast/js/navigator-mimeTypes-length.html
     // asserts that the number of mimetypes handled by plugins should be
     // greater than the number of plugins.  This isn't true if we're