When did relro, now, and nodlopen come into being?

[Jeffrey Walton]

I've been searching for their existence/creation on the web and in:

http://gcc.gnu.org/gcc-4.0/changes.html
http://gcc.gnu.org/gcc-4.1/changes.html
http://gcc.gnu.org/gcc-4.2/changes.html
http://gcc.gnu.org/gcc-4.3/changes.html
http://gcc.gnu.org/gcc-4.4/changes.html
http://gcc.gnu.org/gcc-4.5/changes.html

Does anyone know when the linker switches came into being?

Does anyone know of a GCC feature matrix based on version? I find I am
often searching for a flag/version combination.

Jeff