Thanks to Scott and Jean-Marc for pointing that out, I forgot it.
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First of all, you will need a recent C++ compiler, where recent means
-that the compilers are close to C++ standard conforming like gcc (at
-least 4.3) or clang. Note that the compiler will be used in C++11 mode
-when possible.
+that the compilers are close to C++11 standard conforming like gcc (at
+least 4.3) or clang.
LyX makes great use of the C++ Standard Template Library (STL).
This means that gcc users will have to install the relevant libstdc++