Ultimate++ [http://www.ultimatepp.org/index.html]
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It does have it's own C++ class libs (as Hernan points out), but nothing stops you from using any other class libs like the SDL, or you can roll your own. You can even use boost if you like, but I must say I find some of the supplied classes & techniques to be more useful.
What I appreciate most is it's brilliant integration with the debugger and very complete context-sensitive editor. It uses the standard compiler & debugger (gcc, g++, gdb) on Linux and the MS compiler/debugger on that platform.
The only (very small) gripe I have is the home-made names for projects (called Nest's & so forth). That is unnecessary and may even be off-putting to serious developers, but they are only names & I find I can easily ignore it.
