diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index c73f9bc005aece79b96b55faefee46fc359e4712..d841b6fa8b1d91efb7cdef0b3a7c2eb121ea2de4 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -1325,11 +1325,16 @@ generate_series_step_numeric(PG_FUNCTION_ARGS)
/*
* Use fctx to keep state from call to call. Seed current with the
- * original start value.
+ * original start value. We must copy the start_num and stop_num
+ * values rather than pointing to them, since we may have detoasted
+ * them in the per-call context.
*/
- init_var_from_num(start_num, &fctx->current);
- init_var_from_num(stop_num, &fctx->stop);
+ init_var(&fctx->current);
+ init_var(&fctx->stop);
init_var(&fctx->step);
+
+ set_var_from_num(start_num, &fctx->current);
+ set_var_from_num(stop_num, &fctx->stop);
set_var_from_var(&steploc, &fctx->step);
funcctx->user_fctx = fctx;
diff --git a/src/test/regress/expected/numeric.out b/src/test/regress/expected/numeric.out
index ee6cb50d5a60af688b2e1dc6c17dbce074af51fa..9d6814564df961c4dd4e6d449db3d32a9efe0894 100644
--- a/src/test/regress/expected/numeric.out
+++ b/src/test/regress/expected/numeric.out
@@ -1461,3 +1461,41 @@ select (i / (10::numeric ^ 131071))::numeric(1,0)
9
(4 rows)
+-- Check usage with variables
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(i,3) j;
+ i | j
+---+---
+ 1 | 1
+ 1 | 2
+ 1 | 3
+ 2 | 2
+ 2 | 3
+ 3 | 3
+(6 rows)
+
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(1,i) j;
+ i | j
+---+---
+ 1 | 1
+ 2 | 1
+ 2 | 2
+ 3 | 1
+ 3 | 2
+ 3 | 3
+(6 rows)
+
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(1,5,i) j;
+ i | j
+---+---
+ 1 | 1
+ 1 | 2
+ 1 | 3
+ 1 | 4
+ 1 | 5
+ 2 | 1
+ 2 | 3
+ 2 | 5
+ 3 | 1
+ 3 | 4
+(10 rows)
+
diff --git a/src/test/regress/sql/numeric.sql b/src/test/regress/sql/numeric.sql
index a7e92ac3ccf9dc080def867c49e7685af34c3b00..1633e4c375244f35b517d7a699b2a7c8ea7d3225 100644
--- a/src/test/regress/sql/numeric.sql
+++ b/src/test/regress/sql/numeric.sql
@@ -854,3 +854,7 @@ select (i / (10::numeric ^ 131071))::numeric(1,0)
from generate_series(6 * (10::numeric ^ 131071),
9 * (10::numeric ^ 131071),
10::numeric ^ 131071) as a(i);
+-- Check usage with variables
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(i,3) j;
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(1,i) j;
+select * from generate_series(1::numeric, 3::numeric) i, generate_series(1,5,i) j;