diff options
Diffstat (limited to 'gdb/doc/gdb.texinfo')
| -rw-r--r-- | gdb/doc/gdb.texinfo | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index dfc6e81..1a0e9d2 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -3211,6 +3211,16 @@ expression can use any operators valid in the program's native language (@pxref{Languages}). @end itemize +You can set a watchpoint on an expression even if the expression can +not be evaluated yet. For instance, you can set a watchpoint on +@samp{*global_ptr} before @samp{global_ptr} is initialized. +@value{GDBN} will stop when your program sets @samp{global_ptr} and +the expression produces a valid value. If the expression becomes +valid in some other way than changing a variable (e.g.@: if the memory +pointed to by @samp{*global_ptr} becomes readable as the result of a +@code{malloc} call), @value{GDBN} may not stop until the next time +the expression changes. + @cindex software watchpoints @cindex hardware watchpoints Depending on your system, watchpoints may be implemented in software or @@ -3338,17 +3348,6 @@ exhaust the resources available for hardware-assisted watchpoints. That's because @value{GDBN} needs to watch every variable in the expression with separately allocated resources. -The SPARClite DSU will generate traps when a program accesses some data -or instruction address that is assigned to the debug registers. For the -data addresses, DSU facilitates the @code{watch} command. However the -hardware breakpoint registers can only take two data watchpoints, and -both watchpoints must be the same kind. For example, you can set two -watchpoints with @code{watch} commands, two with @code{rwatch} commands, -@strong{or} two with @code{awatch} commands, but you cannot set one -watchpoint with one command and the other with a different command. -@value{GDBN} will reject the command if you try to mix watchpoints. -Delete or disable unused watchpoint commands before setting new ones. - If you call a function interactively using @code{print} or @code{call}, any watchpoints you have set will be inactive until @value{GDBN} reaches another kind of breakpoint or the call completes. |