diff --git a/configure/os/CONFIG.Common.linux-x86_64 b/configure/os/CONFIG.Common.linux-x86_64
index 564828b47..f1c7a2f5b 100644
--- a/configure/os/CONFIG.Common.linux-x86_64
+++ b/configure/os/CONFIG.Common.linux-x86_64
@@ -16,9 +16,9 @@ ARCH_DEP_CPPFLAGS += -D_X86_64_
 ARCH_DEP_CFLAGS += -m64
 ARCH_DEP_LDFLAGS += -m64
 
-#ifeq ($(BUILD_CLASS),CROSS)
-#  VALID_BUILDS = Ioc
-#endif
+ifeq ($(BUILD_CLASS),CROSS)
+  VALID_BUILDS = Ioc
+endif
 
 # If your crosscompiler name has a GNU target prefix like <gnutarget>-gcc,
 # e.g. x86_64-redhat-linux-gcc, put a GNU_TARGET definition in