Macro C2_PLANE_AT error about cute_headers HOT 8 CLOSED

What I wanted to tell that just adding (c2h) is a wrong fix. It won't work, for example, for MSVC when compiling as C++ code: https://godbolt.org/g/VdV9Ek

For C code it is OK fix - both MSVC and GCC supports this kind of C99 initializer.

Proper way is to create a new temporary local variable or change C2_PLANE_AT to a function.

from cute_headers.

I checked the lines where C2_PLANE_AT is used and I found that you are using the macro to initialize structures (c2h). So, I think that just replacing:

#define C2_PLANE_AT( p, i ) { (p)->norms[ i ], c2Dot( (p)->norms[ i ], (p)->verts[ i ] ) }

with:

#define C2_PLANE_AT( p, i ) (c2h){ p->norms[ i ], c2Dot( p->norms[ i ], p->verts[ i ] ) }

Seems to solve the problem. Apparently, GCC needs to know that the braces "{...}" represent a c2h structure.

Edit: I sent a pull request (#21) with the change.

from cute_headers.

It works with MSVC because it enables C++1x by default. With GCC it works if you use C++11 (or newer) - -std=c++11

from cute_headers.

Probably works only with C++, then. I'm using C. I tried with both -std=c99 and -std=c11, but it didn't work. I found earlier that it would work with extensions, but that would not be ANSI/ISO and extensions aren't that widely used.

Platform: Linux
Compiler: GCC 6.3.1

from cute_headers.

Yes, with C this won't work unless it is used directly in initializer:

c2h t = C2_PLANE_AT(...);

This is not different from MSVC. It works there exactly the same as in GCC.

from cute_headers.

Yes, there's one case in particular that the macro isn't used for initialization:

c2h h = c2Mulxh( x, C2_PLANE_AT( p, i ) );

That's why adding the (c2h) fixed. The other cases are ok (all using for initialization).

from cute_headers.

Agreed. Changing C2_PLANE_AT to a function seems to be more reasonable to guarantee the library is cross-platform.

Edit:
I tried the following, as function:

c2h C2_PLANE_AT( const c2Poly* p, const int i )
{
	c2h h = { p->norms[ i ], c2Dot( (p)->norms[ i ], (p)->verts[ i ] ) };
	return h;
}

It worked here on Linux (GCC), and seems to work with MSVC, too (https://godbolt.org/g/3BeHdF). Confirmation needed.

from cute_headers.

Good change, thanks! I'll add you both as contributors.

from cute_headers.