drop_func_if_not_exists_fix.patch

diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 4661fc4f62..070701044b 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -2053,12 +2053,15 @@ LookupFuncName(List *funcname, int nargs, const Oid *argtypes, bool noError)
 		{
 			if (clist->next)
 			{
-				if (!noError)
-					ereport(ERROR,
-							(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
-							 errmsg("function name \"%s\" is not unique",
-									NameListToString(funcname)),
-							 errhint("Specify the argument list to select the function unambiguously.")));
+				/*
+				 * Raise an error regardless of if noError is set if there are
+				 * multiple matching functions.
+				 */
+				ereport(ERROR,
+						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+							errmsg("function name \"%s\" is not unique",
+								NameListToString(funcname)),
+							errhint("Specify the argument list to select the function unambiguously.")));
 			}
 			else
 				return clist->oid;
diff --git a/src/test/regress/expected/drop_if_exists.out b/src/test/regress/expected/drop_if_exists.out
index b80c5ed2d8..dd4e6c0f6d 100644
--- a/src/test/regress/expected/drop_if_exists.out
+++ b/src/test/regress/expected/drop_if_exists.out
@@ -138,6 +138,16 @@ DROP FUNCTION test_function_exists(int, text, int[]);
 ERROR:  function test_function_exists(integer, text, integer[]) does not exist
 DROP FUNCTION IF EXISTS test_function_exists(int, text, int[]);
 NOTICE:  function test_function_exists(pg_catalog.int4,text,pg_catalog.int4[]) does not exist, skipping
+-- Ensure we still receive an ambiguous function error when there are
+-- multiple matching functions.
+CREATE FUNCTION test_ambiguous_funcname(int) returns int as $$ select $1; $$ language sql;
+CREATE FUNCTION test_ambiguous_funcname(text) returns text as $$ select $1; $$ language sql;
+DROP FUNCTION IF EXISTS test_ambiguous_funcname;
+ERROR:  function name "test_ambiguous_funcname" is not unique
+HINT:  Specify the argument list to select the function unambiguously.
+-- cleanup
+DROP FUNCTION test_ambiguous_funcname(int);
+DROP FUNCTION test_ambiguous_funcname(text);
 -- aggregate
 DROP AGGREGATE test_aggregate_exists(*);
 ERROR:  aggregate test_aggregate_exists(*) does not exist
diff --git a/src/test/regress/sql/drop_if_exists.sql b/src/test/regress/sql/drop_if_exists.sql
index c1d30bc4a5..33f513e436 100644
--- a/src/test/regress/sql/drop_if_exists.sql
+++ b/src/test/regress/sql/drop_if_exists.sql
@@ -153,6 +153,17 @@ DROP FUNCTION IF EXISTS test_function_exists();
 DROP FUNCTION test_function_exists(int, text, int[]);
 DROP FUNCTION IF EXISTS test_function_exists(int, text, int[]);
 
+-- Ensure we still receive an ambiguous function error when there are
+-- multiple matching functions.
+CREATE FUNCTION test_ambiguous_funcname(int) returns int as $$ select $1; $$ language sql;
+CREATE FUNCTION test_ambiguous_funcname(text) returns text as $$ select $1; $$ language sql;
+DROP FUNCTION IF EXISTS test_ambiguous_funcname;
+
+-- cleanup
+DROP FUNCTION test_ambiguous_funcname(int);
+DROP FUNCTION test_ambiguous_funcname(text);
+
+
 -- aggregate
 DROP AGGREGATE test_aggregate_exists(*);
 DROP AGGREGATE IF EXISTS test_aggregate_exists(*);