Re: GNUstep Make not adding -fblocks

[Richard Frith-Macdonald]

On 15 Feb 2011, at 16:10, David Chisnall wrote:

> I am no good at autoconf, but as a simple test, you can try this file:
> 
> void(^block)(void) = ^(void) {};
> 
> $(CC) -c block.c
> 
> This may Just Work™ - it will on OS X with both clang and Apple gcc.  If so, 
> that's great.  If not (exit code from the compiler is not 0), then try:
> 
> $(CC) -c block.c -fblocks
> 
> If this works, then add -fblocks to CFLAGS and OBJCFLAGS (and maybe CXXFLAGS).
> 
> Did you take a look at the exception test I sent you a mail about?

I can't see that in my email archive ... mybe I accidentally deleted it, or 
perhaps it was a private email to Nicola.

> It seems that the configure script is testing whether exceptions work, then 
> deciding that, even though they do, it won't let you use them because it 
> doesn't like the version of GCC that you have.

That may well be the case ... because we don't just need to check that we can 
throw/catch exceptions, we also need to check that we can set a handler for 
uncaught exceptions, and it may well have been a lot easier to just test for 
the version of gcc which added support for that to the runtime than to check to 
see what really happens.

So, a good test for exception support would check both that the compiler 
generates exception code and that the runtime supports setting a handler for 
uncaught exceptions (and that both actually work).
I seem to remember hacking some sort of test into the base config scripts, but 
I don't recall whether it was actually what I'd call a good one.