Fix bug #68882. Don't build xinerama support since it crashes the dynamic loader on stock RH 7.0. Add an explicit --enable-xinerama flag. r=cls

configure.in

@@ -1071,11 +1071,6 @@ then
         $XLIBS $XEXT_LIBS)
     AC_CHECK_HEADER(X11/extensions/Xinerama.h)
 
-    if test -n "$MOZ_XINERAMA_LIBS" && test -n "$ac_cv_header_X11_extensions_Xinerama_h"; then
-      MOZ_ENABLE_XINERAMA=1
-      AC_DEFINE(MOZ_ENABLE_XINERAMA)
-    fi
-        
 	LDFLAGS="$_SAVE_LDFLAGS"
 
 	dnl ========================================================
@@ -1102,6 +1097,29 @@ then
 	  [	MOZ_WIDGET_TOOLKIT="gtk" ])
 fi # $no_x
 
+dnl ========================================================
+dnl =
+dnl = --enable-xinerama
+dnl =
+dnl = This turns on xinerama support.  We just can't use the
+dnl = autodetection of the libraries since on Red Hat 7 linking with
+dnl = Xinerama crashes the dynamic loader.  Make people turn it on
+dnl = explicitly.  The autodetection is done above in the Xlib
+dnl = detection routines.
+dnl =
+dnl ========================================================
+
+
+MOZ_ARG_ENABLE_BOOL(xinerama,
+[  --enable-xinerama       Enable Xinerama support
+                           ( not safe for Red Hat 7.0 ) ],
+  [ if test -n "$MOZ_XINERAMA_LIBS" && \
+      test -n "$ac_cv_header_X11_extensions_Xinerama_h"; then
+        MOZ_ENABLE_XINERAMA=1
+        AC_DEFINE(MOZ_ENABLE_XINERAMA)
+    fi ]
+])
+
 
 MOZ_WIDGET_TOOLKIT_LDFLAGS='-lwidget_$(MOZ_WIDGET_TOOLKIT)'
 MOZ_GFX_TOOLKIT_LDFLAGS='-lgfx_$(MOZ_WIDGET_TOOLKIT) $(MOZ_XLIBRGB_LDFLAGS)'

gfx/src/gtk/Makefile.in

@@ -62,9 +62,13 @@ CXXFLAGS	+= $(TK_CFLAGS)
 CFLAGS		+= $(TK_CFLAGS)
 endif
 
+ifdef MOZ_ENABLE_XINERAMA
+GFX_XINERAMA_LIBS += $(MOZ_XINERAMA_LIBS)
+endif
+
 EXTRA_DSO_LDOPTS += $(MOZ_COMPONENT_LIBS) \
 		-lgkgfx \
-		$(MOZ_XINERAMA_LIBS) \
+		$(GFX_XINERAMA_LIBS) \
 		-lgtksuperwin \
 		$(MOZ_JS_LIBS) \
 		$(NULL)