Fixed support for building with glibc >= 2.34.

This resolves issue #3.

Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
(cherry picked from commit b7e7bb99e1)

ConfigureChecks.cmake

@@ -53,7 +53,9 @@ if( BUILD_KGTK_GTK2 )
 
   check_library_exists( "${CMAKE_DL_LIBS}" _dl_sym "" HAVE_DL_SYM )
   if( NOT HAVE_DL_SYM )
-    tde_message_fatal( "The DL library seems no longer contains _dl_sym function" )
+    message( WARNING, "_dl_sym is requested but not found on your system.\n"
+                      "Some functionality may not be available unless your\n"
+                      "system has glibc 2.34 or greater." )
   endif()
 
 endif()

config.h.cmake

@@ -13,3 +13,6 @@
 #cmakedefine HAVE_STRUCT_UCRED 1
 
 #define VERSION "@KGTK_VERSION_FULL@"
+
+/* Define if you have the '_dl_sym' function */
+#cmakedefine HAVE_DL_SYM 1

gtk2/kgtk2.c

@@ -76,7 +76,9 @@ TODO
 /*
  * For SWT apps (e.g. eclipse) we need to override dlsym.
  */
+#ifdef HAVE_DL_SYM
 extern void *_dl_sym(void *, const char *, void *);
+#endif
 static void * real_dlsym (void *handle, const char *name);
 
 typedef enum
@@ -2246,7 +2248,11 @@ static void * real_dlsym(void *handle, const char *name)
 	if (!realFunction)
 	{
 		// Get the real dlsym function
+#ifdef HAVE_DL_SYM
 		realFunction = _dl_sym(RTLD_NEXT, "dlsym", dlsym);
+#else
+		realFunction = dlvsym(RTLD_NEXT, "dlsym", "GLIBC_2.2.5");
+#endif
 	}
 
 	if (realFunction)