"error: initializer element is not a compile-time constant"

Hi folks,

the following file compiles fine with gcc (4.1.2) but errors with clang (108237). It's preprocessed source, and I've been too lazy to isolate a short test case, so apologies.

http://yoyodyne.ath.cx/tmp/constant.c

Output:

I think the particular folding required to implement the pointer
subtraction used here isn't implemented yet. Feel free to file a bug,
or if you want to look into it yourself, the relevant code is
ExprConstant.cpp.

-Eli