Re: Add a __nowarn__ keyword

[Gabriel Dos Reis <gdr@cs.tamu.edu>]

On Thu, 9 Aug 2007, DJ Delorie wrote:

| 
| > and use the typedef instead?
| 
| What, you don't like all those "structs" around?  ;-)

:-) :-)

As you probably know by now, my brain has been altered by C++ :-)

| > Is it correct that the "user interface" now is to say
| >   
| >     #pragma GCC push
| 
| $pragma GCC diagnostics push
| 
| > ?
| 
| Yes.
| 
| > If yes, is the "push" necessary?  Can we make it implicit?
| 
| So, a pop with no corresponding push, restores to... what?  The way
| the code is now, if you don't push or save, it never even starts the
| chain - it doesn't know the difference between a command line setting
| and a #pragma without a push.  Thus, a pop wouldn't do anything
| anyway.
| 
| I think what you want is, an unmatched pop restores the command line
| settings, yes?  To do that, we'd need two things:
| 
| 1. Something in gcc does the implicit save to start the chain, so that
|    all #pragma changes are in the chain and not the table.
| 
| 2. An unmatched pop points you back at the head of the chain, which is
|    a no-op state created by that save.
| 
| But then, there would be no way to restore some project-wide settings
| pulled in by a #include.
| 
| Or did you mean that a pop always pops just ONE #pragma?  The current
| structure allows that, easier if we move the state struct to
| diagnostics.h.  Then, you just restore to state->previous.  But is
| that a pop, or an undo?


What I have in mind is something like this:

  1. When we see

            #pragma GCC diagnostics foo

     we implicitly save thre current state, push a new one and modify
     that copy to match the requested setting foo.

  2.  When we see

            #pragma GCC diagnostics restore


      we pop the stack and restore the state to the previously known
      state.

Is your point that that scheme is too simplistic to cover all we
want or we would like to support?


-- Gaby