diff options
Diffstat (limited to 'gdb/doc')
| -rw-r--r-- | gdb/doc/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/doc/gdb.texinfo | 23 |
2 files changed, 22 insertions, 7 deletions
diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog index 62bb5e2..94272d1 100644 --- a/gdb/doc/ChangeLog +++ b/gdb/doc/ChangeLog @@ -1,3 +1,9 @@ +2005-04-01 Eli Zaretskii <eliz@gnu.org> + + * gdb.texinfo (Set Watchpoints): Document can-use-hw-watchpoints. + Rearrange index entries and improve wording about support for + hardware watchpoints. + 2005-03-10 Bob Rossi <bob@brasko.net> * gdb.texinfo: Update copyright diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 97b58f8..1df91d8 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -2741,12 +2741,12 @@ You can see these breakpoints with the @value{GDBN} maintenance command @subsection Setting watchpoints @cindex setting watchpoints -@cindex software watchpoints -@cindex hardware watchpoints You can use a watchpoint to stop execution whenever the value of an expression changes, without having to predict a particular place where this may happen. +@cindex software watchpoints +@cindex hardware watchpoints Depending on your system, watchpoints may be implemented in software or hardware. @value{GDBN} does software watchpointing by single-stepping your program and testing the variable's value each time, which is hundreds of @@ -2754,10 +2754,9 @@ times slower than normal execution. (But this may still be worth it, to catch errors where you have no clue what part of your program is the culprit.) -On some systems, such as HP-UX, @sc{gnu}/Linux and some other x86-based targets, -@value{GDBN} includes support for -hardware watchpoints, which do not slow down the running of your -program. +On some systems, such as HP-UX, @sc{gnu}/Linux and most other +x86-based targets, @value{GDBN} includes support for hardware +watchpoints, which do not slow down the running of your program. @table @code @kindex watch @@ -2785,7 +2784,17 @@ watchpoints execute very quickly, and the debugger reports a change in value at the exact instruction where the change occurs. If @value{GDBN} cannot set a hardware watchpoint, it sets a software watchpoint, which executes more slowly and reports the change in value at the next -statement, not the instruction, after the change occurs. +@emph{statement}, not the instruction, after the change occurs. + +@vindex can-use-hw-watchpoints +@cindex use only software watchpoints +You can force @value{GDBN} to use only software watchpoints with the +@kbd{set can-use-hw-watchpoints 0} command. With this variable set to +zero, @value{GDBN} will never try to use hardware watchpoints, even if +the underlying system supports them. (Note that hardware-assisted +watchpoints that were set @emph{before} setting +@code{can-use-hw-watchpoints} to zero will still use the hardware +mechanism of watching expressiion values.) When you issue the @code{watch} command, @value{GDBN} reports |