g++ creates several symbols of a const?

Question

In one of my header (C++) files I changed

   #define TIMEOUT 10

to the more(?) C++ way:

const int TIMEOUT = 10;

It seems however, g++(v 4.4.3) now includes this symbol several times in the binary.

$ nm -C build/ipd/ipd |head
08050420 T ToUnixTime
08050470 T ParseTime
080504c0 T ParseISOTime
080518e4 r TIMEOUT
080518ec r TIMEOUT
080518f4 r TIMEOUT
080518fc r TIMEOUT
080503e0 T HandleMessage

How come ?

Answer 1

You have probably included your header in four separate translation units (.cpp files).

Namespace-scope const variables not declared extern are implicitly static, so there will be one for each translation unit in which the header is included.