Chapter 22. Deprecated Functionality in Red Hat Enterprise Linux 7

Symbols from libraries linked as dependencies no longer resolved by ld

Previously, the ld linker resolved any symbols present in any linked library, even if some libraries were linked only implicitly as dependencies of other libraries. This allowed developers to use symbols from the implicitly linked libraries in application code and omit explicitly specifying these libraries for linking.
For security reasons, ld has been changed to not resolve references to symbols in libraries linked implicitly as dependencies.
As a result, linking with ld fails when application code attempts to use symbols from libraries not declared for linking and linked only implicitly as dependencies. To use symbols from libraries linked as dependencies, developers must explicitly link against these libraries as well.
To restore the previous behavior of ld, use the -copy-dt-needed-entries command-line option. (BZ#1292230)

Windows guest virtual machine support limited

As of Red Hat Enterprise Linux 7, Windows guest virtual machines are supported only under specific subscription programs, such as Advanced Mission Critical (AMC).