diff --git a/contrib/pgcrypto/pgcrypto.c b/contrib/pgcrypto/pgcrypto.c
index 24019f82893..2756900077c 100644
--- a/contrib/pgcrypto/pgcrypto.c
+++ b/contrib/pgcrypto/pgcrypto.c
@@ -492,6 +492,7 @@ pg_check_fipsmode(PG_FUNCTION_ARGS)
 	PG_RETURN_BOOL(CheckFIPSMode());
 }
 
+pg_attribute_no_sanitize_function()
 static void *
 find_provider(text *name,
 			  PFN provider_lookup,
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 4207f0e0e08..5c1eaadd442 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -6574,6 +6574,7 @@ heap_abort_speculative(Relation relation, const ItemPointerData *tid)
  * consequence that the table's next VACUUM could see the table's relfrozenxid
  * move forward between vacuum_get_cutoffs() and finishing.
  */
+pg_attribute_no_sanitize_function()
 bool
 heap_inplace_lock(Relation relation,
 				  HeapTuple oldtup_ptr, Buffer buffer,
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 9512a6a824a..678b9a046ce 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -2099,6 +2099,7 @@ check_functions_in_node(Node *node, check_function_callback checker,
  * uses, but may need to be revisited in future.
  */
 
+pg_attribute_no_sanitize_function()
 bool
 expression_tree_walker_impl(Node *node,
 							tree_walker_callback walker,
@@ -2704,6 +2705,7 @@ expression_tree_walker_impl(Node *node,
  * which is the bitwise OR of flag values to add or suppress visitation of
  * indicated items.  (More flag bits may be added as needed.)
  */
+pg_attribute_no_sanitize_function()
 bool
 query_tree_walker_impl(Query *query,
 					   tree_walker_callback walker,
@@ -2828,6 +2830,7 @@ range_table_walker_impl(List *rtable,
 /*
  * Some callers even want to scan the expressions in individual RTEs.
  */
+pg_attribute_no_sanitize_function()
 bool
 range_table_entry_walker_impl(RangeTblEntry *rte,
 							  tree_walker_callback walker,
@@ -2956,6 +2959,7 @@ range_table_entry_walker_impl(RangeTblEntry *rte,
  * and doing the right thing.
  */
 
+pg_attribute_no_sanitize_function()
 Node *
 expression_tree_mutator_impl(Node *node,
 							 tree_mutator_callback mutator,
@@ -3783,6 +3787,7 @@ expression_tree_mutator_impl(Node *node,
  * it to be modified in-place; they must pass QTW_DONT_COPY_QUERY in flags.
  * All modified substructure is safely copied in any case.
  */
+pg_attribute_no_sanitize_function()
 Query *
 query_tree_mutator_impl(Query *query,
 						tree_mutator_callback mutator,
@@ -3874,6 +3879,7 @@ query_tree_mutator_impl(Query *query,
  * a query's rangetable.  This is split out since it can be useful on
  * its own.
  */
+pg_attribute_no_sanitize_function()
 List *
 range_table_mutator_impl(List *rtable,
 						 tree_mutator_callback mutator,
@@ -3952,6 +3958,7 @@ range_table_mutator_impl(List *rtable,
  * the recursion when the walker's normal change of state is not appropriate
  * for the outermost Query node.
  */
+pg_attribute_no_sanitize_function()
 bool
 query_or_expression_tree_walker_impl(Node *node,
 									 tree_walker_callback walker,
@@ -3975,6 +3982,7 @@ query_or_expression_tree_walker_impl(Node *node,
  * the recursion when the mutator's normal change of state is not appropriate
  * for the outermost Query node.
  */
+pg_attribute_no_sanitize_function()
 Node *
 query_or_expression_tree_mutator_impl(Node *node,
 									  tree_mutator_callback mutator,
@@ -4006,6 +4014,7 @@ query_or_expression_tree_mutator_impl(Node *node,
  * because this is used mainly during analysis of CTEs, and only DML
  * statements can appear in CTEs.
  */
+pg_attribute_no_sanitize_function()
 bool
 raw_expression_tree_walker_impl(Node *node,
 								tree_walker_callback walker,
@@ -4729,6 +4738,7 @@ raw_expression_tree_walker_impl(Node *node,
  * The walker has already visited the current node, and so we need only
  * recurse into any sub-nodes it has.
  */
+pg_attribute_no_sanitize_function()
 bool
 planstate_tree_walker_impl(PlanState *planstate,
 						   planstate_tree_walker_callback walker,
@@ -4813,6 +4823,7 @@ planstate_tree_walker_impl(PlanState *planstate,
 /*
  * Walk a list of SubPlans (or initPlans, which also use SubPlan nodes).
  */
+pg_attribute_no_sanitize_function()
 static bool
 planstate_walk_subplans(List *plans,
 						planstate_tree_walker_callback walker,
@@ -4835,6 +4846,7 @@ planstate_walk_subplans(List *plans,
  * Walk the constituent plans of a ModifyTable, Append, MergeAppend,
  * BitmapAnd, or BitmapOr node.
  */
+pg_attribute_no_sanitize_function()
 static bool
 planstate_walk_members(PlanState **planstates, int nplans,
 					   planstate_tree_walker_callback walker,
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 08f99dff711..2dc81a8d3b2 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -197,6 +197,7 @@ parse_analyze_varparams(RawStmt *parseTree, const char *sourceText,
  * This variant is used when the caller supplies their own parser callback to
  * resolve parameters and possibly other things.
  */
+pg_attribute_no_sanitize_function()
 Query *
 parse_analyze_withcb(RawStmt *parseTree, const char *sourceText,
 					 ParserSetupHook parserSetup,
diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c
index f6fc6271a2e..0db984a26c0 100644
--- a/src/backend/utils/hash/dynahash.c
+++ b/src/backend/utils/hash/dynahash.c
@@ -898,6 +898,7 @@ hash_search(HTAB *hashp,
 									   foundPtr);
 }
 
+pg_attribute_no_sanitize_function()
 void *
 hash_search_with_hash_value(HTAB *hashp,
 							const void *keyPtr,
@@ -1073,6 +1074,7 @@ hash_search_with_hash_value(HTAB *hashp,
  * NB: for a partitioned hashtable, caller must hold lock on both relevant
  * partitions, if the new hash key would belong to a different partition.
  */
+pg_attribute_no_sanitize_function()
 bool
 hash_update_hash_key(HTAB *hashp,
 					 void *existingEntry,
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 594c7a93bba..917cc0ac771 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -633,6 +633,7 @@ MemoryContextUnregisterResetCallback(MemoryContext context,
  * MemoryContextCallResetCallbacks
  *		Internal function to call all registered callbacks for context.
  */
+pg_attribute_no_sanitize_function()
 static void
 MemoryContextCallResetCallbacks(MemoryContext context)
 {
diff --git a/src/include/c.h b/src/include/c.h
index 7a2154ab585..95e71d7e612 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -277,6 +277,22 @@ extern "C++"
 #define pg_attribute_no_sanitize_alignment()
 #endif
 
+/*
+ * Place this macro before functions that intentionally call through a
+ * function pointer whose type does not exactly match the called function.
+ * The prime examples are the expression tree walkers and mutators, which are
+ * declared with their own concrete node and context types and cast to a
+ * generic signature.  That is, strictly speaking, undefined behavior, but it
+ * is a convenient convention that works in practice.  See also
+ * -Wno-cast-function-type-strict, which disables the corresponding
+ * compile-time warning.
+ */
+#ifdef __clang__
+#define pg_attribute_no_sanitize_function() __attribute__((no_sanitize("function")))
+#else
+#define pg_attribute_no_sanitize_function()
+#endif
+
 /*
  * pg_attribute_nonnull means the compiler should warn if the function is
  * called with the listed arguments set to NULL.  If no arguments are
diff --git a/src/include/executor/execScan.h b/src/include/executor/execScan.h
index 25efc622f88..a5902645543 100644
--- a/src/include/executor/execScan.h
+++ b/src/include/executor/execScan.h
@@ -29,6 +29,7 @@
  * eliminated at compile time, avoiding unnecessary run-time checks and code
  * for cases where EPQ is not required.
  */
+pg_attribute_no_sanitize_function()
 static pg_always_inline TupleTableSlot *
 ExecScanFetch(ScanState *node,
 			  EPQState *epqstate,
diff --git a/src/include/lib/sort_template.h b/src/include/lib/sort_template.h
index 22b2092d03b..960b831d919 100644
--- a/src/include/lib/sort_template.h
+++ b/src/include/lib/sort_template.h
@@ -257,6 +257,7 @@ ST_SCOPE void ST_SORT(ST_ELEMENT_TYPE * first, size_t n
  * Refer to the comment at the top of this file for known caveats to consider
  * when writing inlined comparator functions.
  */
+pg_attribute_no_sanitize_function()
 static pg_noinline ST_ELEMENT_TYPE *
 ST_MED3(ST_ELEMENT_TYPE * a,
 		ST_ELEMENT_TYPE * b,
@@ -288,6 +289,7 @@ ST_SWAPN(ST_POINTER_TYPE * a, ST_POINTER_TYPE * b, size_t n)
 /*
  * Sort an array.
  */
+pg_attribute_no_sanitize_function()
 ST_SCOPE void
 ST_SORT(ST_ELEMENT_TYPE * data, size_t n
 		ST_SORT_PROTO_ELEMENT_SIZE
diff --git a/src/pl/plpgsql/src/pl_funcs.c b/src/pl/plpgsql/src/pl_funcs.c
index 92cd9116c0e..e15962563f5 100644
--- a/src/pl/plpgsql/src/pl_funcs.c
+++ b/src/pl/plpgsql/src/pl_funcs.c
@@ -360,6 +360,7 @@ typedef void (*plpgsql_expr_walker_callback) (PLpgSQL_expr *expr,
 	plpgsql_statement_tree_walker_impl(s, (plpgsql_stmt_walker_callback) (sw), \
 									   (plpgsql_expr_walker_callback) (ew), c)
 
+pg_attribute_no_sanitize_function()
 static void
 plpgsql_statement_tree_walker_impl(PLpgSQL_stmt *stmt,
 								   plpgsql_stmt_walker_callback stmt_callback,