Re: [PATCH][C] Fix GNU extern inline heuristic again (fix C++ memory usage regression)

[Paolo Bonzini <paolo dot bonzini at lu dot unisi dot ch>]

Ian Lance Taylor wrote:
> Paolo Bonzini <bonzini@gnu.org> writes:
>
> > > Richard, the patch is OK.
> > I think we should add a note to the manual that GNU "extern inline"
> > functions are always inlined.
>
> By my reading, the documentation already says that.  Where you
> thinking of a specific place to change?

Looking at 4.2 documentation, it never mentioned different inlining 
policies for "GNU extern inline" vs. other inline functions.

I was thinking that, where it says "The definition in the header file 
will cause most calls to the function to be inlined.", we could add 
"because `extern inline' functions are always inlined independent of the 
usual heuristics to limit code growth and of optimization being enabled."

At the end of the paragraph, where "always_inline" is documented, it 
says "GCC does not inline any functions when not optimizing unless you 
specify the `always_inline' attribute".  We should say, "When not 
optimizing, GCC only inlines functions that use the GNU `extern inline' 
extension, or that specify the `always_inline' attribute".

Also, Richi, does your patch change the behavior of GCC with respect to 
recursive `extern inline' functions?

Paolo