From: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
Date: Mon, 7 Sep 2009 19:27:08 +0000 (+0200)
Subject: Allow dlopen self test to work with gcc's -fvisibility=hidden.
X-Git-Tag: v2.2.7b~60
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b03736353b6d478a68bfc19c017605eb21a3edce;p=thirdparty%2Flibtool.git

Allow dlopen self test to work with gcc's -fvisibility=hidden.

* libltdl/m4/libtool.m4 (_LT_TRY_DLOPEN_SELF): Declare default
visibility for the symbol we are going to test dlopen (NULL)
when a GCC version is used that understands the visibility
attribute, under the assumption that if -fvisibility=hidden
will be used, the user code will be sufficiently annotated
for visibility of needed symbols from the main executable.
* THANKS: Update.
Report by Josh Hursey against OpenMPI.

Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
---

diff --git a/ChangeLog b/ChangeLog
index 26afae704..d3e924fee 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2009-09-07  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
+	Allow dlopen self test to work with gcc's -fvisibility=hidden.
+	* libltdl/m4/libtool.m4 (_LT_TRY_DLOPEN_SELF): Declare default
+	visibility for the symbol we are going to test dlopen (NULL)
+	when a GCC version is used that understands the visibility
+	attribute, under the assumption that if -fvisibility=hidden
+	will be used, the user code will be sufficiently annotated
+	for visibility of needed symbols from the main executable.
+	* THANKS: Update.
+	Report by Josh Hursey against OpenMPI.
+
 	Fix and split recent testsuite addition for compile/link flags.
 	* tests/flags.at (passing flags through libtool): Split into ...
 	(passing CC flags through libtool)
diff --git a/THANKS b/THANKS
index 935388598..8baf7f412 100644
--- a/THANKS
+++ b/THANKS
@@ -110,6 +110,7 @@
   John Bowler			jbowler@acm.org
   John R. Cary			cary@txcorp.com
   John Wolfe			jlw@sco.com
+  Josh Hursey			jjhursey@open-mpi.org
   Joseph Beckenbach III		jrb3@best.com
   Lennart Poettering		lennart@poettering.net
   Karl Berry			karl@freefriends.org
diff --git a/libltdl/m4/libtool.m4 b/libltdl/m4/libtool.m4
index bb1097f2e..662a88b12 100644
--- a/libltdl/m4/libtool.m4
+++ b/libltdl/m4/libtool.m4
@@ -1651,7 +1651,13 @@ else
 #  endif
 #endif
 
-void fnord() { int i=42;}
+/* When -fvisbility=hidden is used, assume the code has been annotated
+   correspondingly for the symbols needed.  */
+#if defined(__GNUC__) && (((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3))
+void fnord () __attribute__((visibility("default")));
+#endif
+
+void fnord () { int i=42; }
 int main ()
 {
   void *self = dlopen (0, LT_DLGLOBAL|LT_DLLAZY_OR_NOW);
@@ -1660,7 +1666,11 @@ int main ()
   if (self)
     {
       if (dlsym (self,"fnord"))       status = $lt_dlno_uscore;
-      else if (dlsym( self,"_fnord")) status = $lt_dlneed_uscore;
+      else
+        {
+	  if (dlsym( self,"_fnord"))  status = $lt_dlneed_uscore;
+          else puts (dlerror ());
+	}
       /* dlclose (self); */
     }
   else