Re: [Fxruby-users] FXRuby on QNX

[Lyle J. <ly...@kn...>]

On Feb 12, 2004, at 7:06 PM, Joel VanderWerf wrote:

> Hi, I've got Fox working on QNX6.2.1, and I've got ruby working, but 
> FXRuby doesn't build for me. Anybody else try this?
>
> The problems atm have to so with constness in C++:
>
> /usr/include/string.h: In function `void * memchr(void *, int, 
> unsigned int)':
> /usr/include/string.h:125: declaration of C function `void * 
> memchr(void *, int, unsigned int)' conflicts with
> /usr/include/string.h:49: previous declaration `const void * 
> memchr(const void *, int, unsigned int)' here
>
> ...and more like that
>
> When you include string.h with __cplusplus defined, these declarations 
> become inconsistent. I tried a minimal .cpp example (based on 
> hello.cpp from Fox) that includes "string.h", but couldn't recreate 
> the problem. So probably something is misconfigured in FXRuby, but 
> what precisely...

That's a new one. Which file(s) from FXRuby is it trying to compile 
when you get this error message?

When you compile code with a C++ compiler, the compiler's supposed to 
(internally) define the __cplusplus symbol. And what I would expect to 
see in a header file like string.h, if there is a "C version" of 
memchr() and a "C++ version" of memchr(), would be something like this:

	#ifdef __cplusplus
	// Here's the C++ declaration...
	const void * memchr(const void *, int, unsigned int);
	#else
	/* Here's the C declaration, without const */
	void * memchr(void *, int, unsigned int);
	#endif

That is, I'd expect the compiler to see one or the other, but not both!