GCC Bugzilla – Bug 47605
Document that C_Bool might be the wrong constant for C Booleans
Last modified: 2011-02-04 07:17:13 UTC
James pointed out the following at
c_bool is typically one byte wide, and c_int 4. That means: Most C programs - except of those few which explicitly use _Bool, use a 4 byte and not a 1 byte Boolean variables.
I think one should put a warning into the manual - either in the C Binding part  or in the section about the ISO C Binding constants , or in both.