When using gdb, how to print a part of values in array in Pascal

Question

We know, in C language, if there is an array

int data[100];

then ,in gdb, we can print data[4] to data[14] by typing:

print *(data+4)@11

so, the question is: when we program in Pascal language, we may have an array:

var
   data: array[0..100] of Integer;

when we debug it in gdb, how can we print the value from data[4] to data[14]?

Thank you very much.

I never tried, but what makes you think that would be different? I guess you should be able to use the same syntax. What have you tried? — Rudy Velthuis
– Rudy Velthuis, Commented Jan 3, 2018 at 8:38
@RudyVelthuis @data[4]^@11 but failed. I had struggled for hours. — Minghang Yang
– Minghang Yang, Commented Jan 3, 2018 at 9:14
But that is a different syntax. What happens if you use the original *(data+4)@11? — Rudy Velthuis
– Rudy Velthuis, Commented Jan 3, 2018 at 12:08
@RudyVelthuis A parse error in expression, near '(data+4)@11' — Minghang Yang
– Minghang Yang, Commented Jan 3, 2018 at 12:13

Tom Tromey · Accepted Answer · 2018-01-04 17:46:41Z

1

There is no way to do this when gdb's language is set to Pascal -- nobody ever implemented this extension in the Pascal expression parser.

One workaround is to print the address of the array, then temporarily switch the language to C and print *(type *)addr @ ....

Another workaround would be to write a new gdb command (either using the CLI or using Python) that does what you like. Or, if you are doing a lot of Pascal debugging, you could implement this extension in gdb -- it isn't hard.

answered Jan 4, 2018 at 17:46

Tom Tromey

22.8k3 gold badges53 silver badges67 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

When using gdb, how to print a part of values in array in Pascal

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related