Fix C23 compiler warning

petere · petere · commit f3834c12afd8 · 2024-11-26T13:36:49.000+01:00
The approach of declaring a function pointer with an empty argument list and hoping that the compiler will not complain about casting it to another type no longer works with C23, because foo() is now equivalent to foo(void). We don't need to do this here. With a few struct forward declarations we can supply a correct argument list without having to pull in another header file. (This is the only new warning with C23. Together with the previous fix a67a496, this makes the whole code compile cleanly under C23.) Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/95c6a9bf-d306-43d8-b880-664ef08f2944%40eisentraut.org Discussion: https://www.postgresql.org/message-id/flat/87o72eo9iu.fsf%40gentoo.org
diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h
@@ -1101,6 +1101,9 @@ typedef struct IndexOptInfo IndexOptInfo;
 #define HAVE_INDEXOPTINFO_TYPEDEF 1
 #endif
 
+struct IndexPath;				/* avoid including pathnodes.h here */
+struct PlannerInfo;				/* avoid including pathnodes.h here */
+
 struct IndexOptInfo
 {
 	pg_node_attr(no_copy_equal, no_read, no_query_jumble)
@@ -1200,7 +1203,7 @@ struct IndexOptInfo
 	bool		amcanmarkpos;
 	/* AM's cost estimator */
 	/* Rather than include amapi.h here, we declare amcostestimate like this */
-	void		(*amcostestimate) () pg_node_attr(read_write_ignore);
+	void		(*amcostestimate) (struct PlannerInfo *, struct IndexPath *, double, Cost *, Cost *, Selectivity *, double *, double *) pg_node_attr(read_write_ignore);
 };
 
 /*
