[Bug c++/52455] Symbolic constant treated as extern when -O not specified resulting in undefined symbol at link

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52455

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-03-02 
09:33:08 UTC ---
This is a FAQ 

http://gcc.gnu.org/wiki/VerboseDiagnostics#undefined_reference_to_.60S::a.27