spgist rangetypes compiler warning (gcc 7.2.0)

Hi,

while compiling on gcc 7.2.0 (on ARM), I got this warning:

rangetypes_spgist.c: In function 'spg_range_quad_inner_consistent':
rangetypes_spgist.c:559:29: warning: comparison between pointer and
zero character constant [-Wpointer-compare]
if (in->traversalValue != (Datum) 0)
^~
rangetypes_spgist.c:559:10: note: did you mean to dereference the
pointer?
if (in->traversalValue != (Datum) 0)
^

I believe we should simply treat the traversalValue as pointer, and
change the condition to

if (in->traversalValue)

Patch attached.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services