None of those variables was referenced in C code, and there are
no GUC variables matching them, so it's a dead code.
Those variables are still referenced in three sets of regression
tests - rangefuncs, xc_limit and xc_sort.
For rangefuncs the reference is however only in one of multiple
possible outputs (and apparently we pick another one), and the
other two regression tests are not part of any test schedule.
bool enable_material = true;
bool enable_mergejoin = true;
bool enable_hashjoin = true;
-#ifdef PGXC
bool enable_fast_query_shipping = true;
-bool enable_remotejoin = true;
-bool enable_remotegroup = true;
-#endif
typedef struct
{
extern bool enable_hashjoin;
#ifdef PGXC
extern bool enable_fast_query_shipping;
-extern bool enable_remotejoin;
-extern bool enable_remotegroup;
+
#endif
extern int constraint_exclusion;