Possibly a symbol generated from a macro, which would make finding it via a simple grep harder

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This doesn't ring a bell, but, on the other hand, I don't recall ever building this stuff with anything else than the final Linaro GCC 4.9 release (e.g., start from the kindle koxtoolchain profile, and just switch to said GCC release in the menuconfig).
And the Ubuntu TCs are generally Not Great (TM) for this stuff (... much like the distro itself. Oops

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