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I run ubuntu 12.04. Recently, I have followed this post and updated GCC to 4.8.1. Now, when I compile with g++, I get compiler output like these:

/usr/include/c++/4.6/bits/stl_algobase.h:743: note:   Profitability threshold = 6
/usr/include/c++/4.6/bits/stl_algobase.h:743: note: Profitability threshold is 6 loop iterations.
/usr/include/c++/4.6/bits/stl_algobase.h:743: note: LOOP VECTORIZED.

My question is why is g++ using the STLs from GCC 4.6? Is this normal or does this show that I didn't updated GCC thoroughly? If the latter, how can I direct g++ to the new STLs?

Edit0: i installed package g++-4.8 (just now, thanks steeldriver) but still get the same messages~

Edit1: I followed kenn's suggestion and just ran sudo ldconfig...but I still get those messages

Thanks in advance,

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Did you also update g++? – steeldriver Apr 2 '14 at 19:51
did you run sudo ldconfig after installation of gcc? – kenn Apr 2 '14 at 20:11
Check with which g++ for the path and see if it's the right path – arsaKasra Apr 2 '14 at 20:21
@arsaKasra; thanks! but how do I do that? – user2413 Apr 2 '14 at 20:23
don't confuse gcc with g++ – kenn Apr 2 '14 at 20:38
up vote 0 down vote accepted

OK, I've answered my question by combining these two answers to related quetions. answer 1: update g++ to g++4.8

answer 2: create new Symlinking

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