Please avoid use of variable length array

[vmo]

While trying to compile with Microsoft Visual, I came across this use of variable length array (in geography_centroid.c) because the compiler doesn't support those.

    case MULTIPOINTTYPE:
    {
        LWMPOINT* mpoints = lwgeom_as_lwmpoint(lwgeom);

        /* average between all points */
        uint32_t size = mpoints->ngeoms;
        POINT3DM points[size];

		uint32_t i;
		for (i = 0; i < size; i++) {
            points[i].x = lwpoint_get_x(mpoints->geoms[i]);
            points[i].y = lwpoint_get_y(mpoints->geoms[i]);
            points[i].m = 1;
        }

		lwpoint_out = geography_centroid_from_wpoints(srid, points, size);
        break;
    }

This is a tad dangerous IMHO with geometries, since they can be arbitrarily large (let's take the geographic centroid of a pointcloud

[vmo]

replace vla with plain old palloc

[strk]

In 16508:

Avoid incompatible automatic variable length array

Patch by vmo
Closes #4059

[strk]

Thanks !

[vmo]

You're very welcome, tracking vla is for the moment the only useful thing visual does.

As a side note: I also have to replace

    const size_t sz=4; 

by

#   define sz 4

if sz is used to dimension an array… because, for visual, sz is not a const expression…

[strk]

vla is not valid ansi either IIRC, so I'm happy to drop

[pramsey]

In 16970:

Remove use of VLA from geography centroid
References #4059