HP gnu source-level debugger 5992-4701 manual Instruction Level Stepping, Deferred watchpoints

Abort gdb command line call? (y or n) y #0 main () at ./address_error.c:41

41 fun (count, count*1.1); (gdb) bt

#0 main () at ./address_error.c:41 (gdb) quit

The program is running. Exit anyway? (y or n) y

14.20 Instruction Level Stepping

During instruction level stepping with nexti and stepi, WDB prints the assembly instruction along with the next source line.

(gdb) stepi 0x101530:0 st4 [r9]=r34 1337 args.argc = argc;

It also prints DOC line information, which includes actual line number and the column number, when debugging a binary with -g -O.

(gdb) stepi ;;; [8, 1] 0x4000820:1 nop.m 0x0

GDB cannot step into a function with no debug information. GDB cannot do a next over a line when there is not debug information. However, the continue command works in such situations.

14.21 Enhanced support for watchpoints and breakpoints

14.21.1 Deferred watchpoints

When you try to set a watchpoint in an expression, HP WDB places a deferred watch- point if HP WDB cannot evaluate the expression. The watchpoint is automatically enabled whenever the expression can be evaluated during the programs execution. This is especially useful when placing the watchpoints on unallocated addresses.

14.21.2 Hardware watchpoints

HP WDB provides support for hardware watchpoints on HP-UX 11.x.

14.21.3 Hardware breakpoints

The hbreak command sets hardware assisted breakpoints.

hbreak args

The arguments (args) is same as that for the break command and the breakpoint is set in the same way. However, the breakpoint uses hardware assisted breakpoint registers. There are only two hardware breakpoints that can be set on Integrity systems. This is useful in ROM code debugging and shared library debugging for libraries, including dld, that are not loaded private.

The normal breakpoints are converted to a hardware breakpoint when WDB cannot set a normal breakpoint in the shared library.

208 HP-UX Configuration-Specific Information