Re: Volatile constants?

[Richard Earnshaw <rearnsha@arm.com>]

> /* Okay I forgot the parenthesis, but that was not my point */
> 
> The GCC manual says "An Inline Function is As Fast As a Macro",
> but when I compile this (as C code), I got error "initializer element is not constant" on
> 's' initialization.
> 
> inline int abs1(int x) {
>     return x<0 ? -x : x;
> }
> #define abs2(x) ((x)<0 ? -(x) : (x))
> 
> int r = abs1(-7);
> int s = abs2(-7);
> 
> Is there any option I have to pass?
> 
> >I don't get that error message. Here is what my compiler says: ...
> 
> Okay you use g++. I use the c compiler.
> g++ don t generate an error (not even a warning) for this,
> but makes an constructor function, 'static_initialization_and_destruction'-something
> That is not what I want and it is NOT as fast as a macro.
> 
> >I think you should upgrade to gcc-2.95.2.
> I compiled with that version, yes
> 
> I ll be glad for any help
> 


An inline function is NOT a macro, it's still a function.  You can't use a 
function as an initializer for a static extent variable in C.

Speed has nothing to do with it; the semantics are different.

Now if the manual said "an inline function is the SAME as a macro", then 
you would have a legitimate complaint.  But it doesn't, so you don't.

R.