c - What is the __builtin_expect() prototype? -

to rid of static code analysis warning (qa-c), need provide function prototype __builtin_expect().

i using windriver diab compiler powerpc. in compiler manual have found following information:

__builtin_expect(long exp, long c): ... exp return value.

so, prototype follows:

long __builtin_expect(long exp, long c); 

however, not compile, getting following error:

error (dcc:1701): invalid types on prototype intrinsic __builtin_expect - when intrinsic enabled, optional user prototype must match

it seems prototype not correct. correct prototype __builtin_expect?

the error message states user prototype optional. should possible define it, right?

you need somehow define __builtin_expect make static analyzer happy, because doesn't know function is. need use #ifdef disable definition when compiling program normally, because compiler not if try define compiler builtins yourself. builtins come compiler not supposed defined in program.

something work:

#ifdef _hey_i_am_running_static_analyzer #define __builtin_expect(e,c) (e) #endif 

i don't know details of how static analyzer works, don't know right macro test in #ifdef. can read documentation of static analyzer find out if defines preprocessor symbols default, or if can tell preprocessor symbols define when run it.