The definition of the macro LBER_INVALID in 'include/lber.h'
mismatched (unbalanced) parentheses, meaning that it cannot be used as
a valid C expression by itself.
Wow. You are the first to notice for 10 years. The test is incomplete
too. I guess I can come up with bit hack for a better test is anyone is
interested, but otherwise we can just delete it.
The macro only existed without a parse error for one month in 1999, in
revision 1.17 through 1.30. Next revision broke it with commit message
"Fix bad LBER_INVALID macro":-)