For the latest (Juno) eclipse cdt the following worked for me, no need to declare __GXX_EXPERIMENTAL_CXX0X__
on myself. This works for the the CDT indexer and as parameter for the compiler:
"your project name" -> right click -> properties:
C/C++ General -> Preprocessor Include Paths, Macros etc. -> switch to the tab named "Providers":
for "Configuration" select "Release" (and afterwards "debug")
switch off all providers and just select "CDT GCC Built-in Compiler Settings"
uncheck "Share setting entries between projects (global provider)"
in the "Command to get compiler specs:" add "-std=c++11" without the quotes (may work with quotes too)
hit apply and close the options
rebuild the index
Now all the c++11 related stuff should be resolved correctly by the indexer.
win7 x64, latest official eclipse with cdt mingw-w64 gcc 4.7.2 from the mingwbuilds project on sourceforge