Virtuoso 7.2.12 crashes with the `SOAP_CLIENT` function.

Environment: Ubuntu 20.04, docker image `openlink/virtuoso-opensource-7:7.2.12`.

PoC:
```sql
SELECT SOAP_CLIENT('1', '1', '1', '-9999999.9999999e-1');
```

Backtrace:
```
#0 0xa58440 (soap_call_schema_prep+0x90)
#1 0xa5c2df (soap_call_prep+0x11f)
#2 0xa5d6a8 (bif_soap_call_new+0x1038)
#3 0x755af4 (ins_call_bif+0xc4)
#4 0x7639b9 (code_vec_run_1+0xdf9)
#5 0x7b9cc1 (qn_input+0x3c1)
#6 0x7cdefa (qr_subq_exec+0x94a)
#7 0x756ab1 (ins_call+0xc91)
#8 0x7637f8 (code_vec_run_1+0xc38)
#9 0x7b9cc1 (qn_input+0x3c1)
#10 0x7cdefa (qr_subq_exec+0x94a)
#11 0x756ab1 (ins_call+0xc91)
#12 0x7584a0 (ins_call_vec+0x320)
#13 0x75bcb5 (code_vec_run_v+0xa25)
#14 0x7b9c8f (qn_input+0x38f)
#15 0x7ba136 (qn_send_output+0x236)
#16 0x82c91d (set_ctr_vec_input+0x99d)
#17 0x7b9cce (qn_input+0x3ce)
#18 0x7cb4bb (qr_exec+0x11db)
#19 0x7d8e56 (sf_sql_execute+0x11a6)
#20 0x7d995e (sf_sql_execute_w+0x17e)
#21 0x7e261d (sf_sql_execute_wrapper+0x3d)
#22 0xe29cec (future_wrapper+0x3fc)
#23 0xe315ee (_thread_boot+0x11e)
#24 0x7f38e7592609 (start_thread+0xd9)
#25 0x7f38e7362353 (clone+0x43)
```
Virtuoso 7.2.12 crashes with the `SOAP_CLIENT` function
This is a GitHub Issue
repo:virtuoso-opensource
owner:openlink
Title : Virtuoso 7.2.12 crashes with the `SOAP_CLIENT` function
Issue date:

--- start body ---
Virtuoso 7.2.12 crashes with the `SOAP_CLIENT` function.

Environment: Ubuntu 20.04, docker image `openlink/virtuoso-opensource-7:7.2.12`.

PoC:
```sql
SELECT SOAP_CLIENT('1', '1', '1', '-9999999.9999999e-1');
```

Backtrace:
```
#0 0xa58440 (soap_call_schema_prep+0x90)
#1 0xa5c2df (soap_call_prep+0x11f)
#2 0xa5d6a8 (bif_soap_call_new+0x1038)
#3 0x755af4 (ins_call_bif+0xc4)
#4 0x7639b9 (code_vec_run_1+0xdf9)
#5 0x7b9cc1 (qn_input+0x3c1)
#6 0x7cdefa (qr_subq_exec+0x94a)
#7 0x756ab1 (ins_call+0xc91)
#8 0x7637f8 (code_vec_run_1+0xc38)
#9 0x7b9cc1 (qn_input+0x3c1)
#10 0x7cdefa (qr_subq_exec+0x94a)
#11 0x756ab1 (ins_call+0xc91)
#12 0x7584a0 (ins_call_vec+0x320)
#13 0x75bcb5 (code_vec_run_v+0xa25)
#14 0x7b9c8f (qn_input+0x38f)
#15 0x7ba136 (qn_send_output+0x236)
#16 0x82c91d (set_ctr_vec_input+0x99d)
#17 0x7b9cce (qn_input+0x3ce)
#18 0x7cb4bb (qr_exec+0x11db)
#19 0x7d8e56 (sf_sql_execute+0x11a6)
#20 0x7d995e (sf_sql_execute_w+0x17e)
#21 0x7e261d (sf_sql_execute_wrapper+0x3d)
#22 0xe29cec (future_wrapper+0x3fc)
#23 0xe315ee (_thread_boot+0x11e)
#24 0x7f38e7592609 (start_thread+0xd9)
#25 0x7f38e7362353 (clone+0x43)
```
--- end body ---
