Error Subscript 1 range error impossible to solve (Alpha VMS 6.2)

[Stephane Boneff]

Hello,

i have a dark problem with a Fortran process.
I have been running fine for years.
Since end of august, it is crashing randomly with error "Subscript 1 range error".

The line :
IF ((val_c(Cowp:Cowp) .NE. ' ') .OR. (Memo(cowp).date_fin_poste .NE. ' ')) THEN

With a .DMP, i verified that every variable is ok (cowp = 6, val_c is a string of 132 long, Memo is a array of 9).
(with Analyze /dump /ima xxxxx)

compil option :
/DEBUG/NOOPT/EXTEND/CHECK=ALL/CONT=60/NOALI/NOWAR

link flag :
DEBUG/TRACE/MAP:HPAPP_OBJ


Since the fist crash, the .EXE has been remake manu time with no change.

It can crash 3 time a day and not crash for 4 days.

One expert of my compagny don't undertand this problem.

Do you have some idea ?

Thanks

[Volker Halle · Accepted solution]

Welcome to the OpenVMS ITRC forum.

Could you please show the real error message (with cut & paste) ?

And also provide a session log file of your analysis session (in an attached .TXT file) ?

'Dark problems' presented with insufficient information may remain a mystery...

Volker.

[labadie_1]

Can you post your version of Fortran ?

$ anal/ima/int sys$system:fortran.exe followed by 4 or 5 returns should show it.

[Steven Schweda]

> $ anal/ima/int sys$system:fortran.exe [...]

"FORTRAN /VERSION" might be easier, if it's
not too old.

[Stephane Boneff]

thanks for your help !

version of Fortran :
DEC Fortran for OpenVMS AXP Systems v6.3-711
(from a .LIS source)


full error message :
%SYSTEM-F-SUBRNG1, subscript 1 range error, PC=0005A564, PS=0000001B
%TRACE-F-TRACEBACK, symbolic stack dump follows
Image Name Module Name Routine Name Line Number rel PC abs PC
CAL_BIL_COW CAL_BIL_COW CAL_BIL_COW 7700 0000A564 0005A564
CAL_BIL_COW 0 000CD5EC 000DD5EC
DEC$FORRTL 0 00072818 00898818
CAL_BIL_COW 0 000CD5EC 000DD5EC
0 85822170 85822170

With the source code, the crash is impossible :

- the index COWP is in a Do 1,MAXI loop (MAXI=9)
- for the array MEMO, the dim is MAXI
- val_c is a 132 long characters string.

what is "analysis session" ?

I only use Analyze /proc with a 51000 blocks dump file (which is impossible to provide here).

I put the .LIS of the source.
(tilt on line 7700)

[Volker Halle]

re: 'analysis session'

Just invoke ANAL/PROC on the dump and examine the current variables, Alpha instruction stream etc. and capture this in a .TXT file (with cut & paste).

Volker.

[Volker Halle]

I'm assuming, the SUBRNG1 error is being generated by the GENTRAP instruction at offset 66D4 (label L$102: in machine code listing).

There are a couple of branches to L$102 in the instruction stream for line 7700. You would have to try to re-do the Alpha instructions in your head and try to figure out, which branch took you to L$102:

In ANAL/PROC, issue the command:

DBG> EXA/INS @PC-30:@PC+10

to identify the instruction stream you're in. Then look at all the registers and the variables.

Volker.

[Stephane Boneff]

the asked data are in the file .TXT


thanks.

[Stephane Boneff]

VMS version : OpenVMS V6.2-1H2

Machine :AlphaStation 400 4/166

memory : 256 Mb


Tell me if you need other information.

[Volker Halle]

Please provide the output of:

DBG> SET LAN MAC
DBG> EXA/INS @PC-20:@PC+10
DBG> EXA @FP+44

Volker.