diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 5db4f5761d..4aa5ed91bd 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -16469,6 +16469,10 @@ dumpAttrDef(Archive *fout, AttrDefInfo *adinfo)
 	if (!adinfo->separate)
 		return;
 
+	/* ALTER COLUMN doesn't support setting a generated column */
+	if (tbinfo->attgenerated[adnum - 1])
+		return;
+
 	q = createPQExpBuffer();
 	delq = createPQExpBuffer();