So just a little terminology to make things clear.  lldb has "breakpoints" 
which are the object you actually make when you do "break set".  Then each 
breakpoint can have a number of "breakpoint locations" which are the places 
that the breakpoint specification resolved to in your program.  Finally, there 
are "breakpoint sites" which are places that we actually insert trap 
instructions to implement the breakpoint locations.  Note that you could have 
many breakpoint locations with the same address, so all those locations would 
share one site.  Having the sites as a separate list is very convenient 
internally, since they can be stored in a nice address sorted list, and it 
makes the lookup from "stop address" to breakpoint efficient.

Anyway, so the "breakpoint site 3" output you are seeing generally only happens 
when we hit a breakpoint site but by the time we get to reporting it we can't 
find the breakpoint location corresponding to that site (maybe the breakpoint 
got deleted in the process of stopping?)

You can try turning on the lldb log for breakpoints to see what this breakpoint 
actually is:

(lldb) log enable lldb breakpoint

Note also, lldb sets some breakpoints for its own purposes (for instance 
breakpoints on the dyld load notification routine so we can find out when new 
shared libraries get loaded.)  That particular breakpoint - which you would 
have hit while loading your dylib - is set to auto-continue without informing 
the upper layers of lldb that it had been hit.  So that shouldn't have 
interrupted the load command.  Of course something might be wrong that is 
defeating that...

Jim

On Aug 10, 2011, at 9:59 AM, Filipe Cabecinhas wrote:

> The problem is that I only placed one breakpoint, how can I have a 
> "breakpoint site 3"? Here's my interaction with lldb:
> 
> ➜  tests ±:(master) ! lldb ./a
> Current executable set to './a' (x86_64).
> (lldb) breakpoint set -n main
> Breakpoint created: 1: name = 'main', locations = 1
> (lldb) run
> DynamicLoaderMacOSXDYLD::PrivateInitialize() process state = launching
> DynamicLoaderMacOSXDYLD::SetNotificationBreakpoint() process state = launching
> Process 81623 launched: '/Users/filipe/src/tests/a' (x86_64)
> Process 81623 stopped
> * thread #1: tid = 0x2d03, 0x0000000100000dd0 a`main + 32 at a.c:13, stop 
> reason = breakpoint 1.1
>     frame #0: 0x0000000100000dd0 a`main + 32 at a.c:13
>    10         
>    11         int main()
>    12         {
> -> 13           int i = ITERS, r = 0;
>    14           clock_t start, end;
>    15         
>    16           r = nyan(1);
> (lldb) process load ~/src/tests/libmylib.dyld
> error: failed to load '~/src/tests/libmylib.dyld': Execution was interrupted, 
> reason: breakpoint site 3.
> The process has been returned to the state before execution.
> (lldb) breakpoint list --full 
> Current breakpoints:
> 1: name = 'main', locations = 1, resolved = 1
>   1.1: where = a`main + 32 at a.c:13, address = 0x0000000100000dd0, resolved, 
> hit count = 1 
> 
> 
> Thanks for the help,
> 
>   Filipe
> 
> On Tue, Aug 9, 2011 at 19:16, Greg Clayton <[email protected]> wrote:
> Internal breakpoints have negative IDs, so this hit one of your breakpoints, 
> breakpoint 3.
> 
> Do a:
> 
> (lldb) breakpoint list --full
> 
> And see which breakpoint it is hitting.
> 
> 
> On Aug 9, 2011, at 4:56 PM, Filipe Cabecinhas wrote:
> 
> > Hi,
> >
> > It seems I forgot to include the patches in this message, sorry about that. 
> > I'm sending them now, along with a patch to report errors when doing a 
> > "process load".
> >
> > I am also not able to do a "process load mylib.dylib", where mylib has this 
> > table (I'm trying to redefine printf):
> > ➜  tests ±:(master) ! nm -m libmylib.dylib
> > 00000f60 (__TEXT,__text) external _printf
> > 00000fa0 (__TEXT,__text) non-external _strlen
> >          (undefined) external _write$UNIX2003 (from libSystem)
> >          (undefined) external dyld_stub_binder (from libSystem)
> >
> > I get the error:
> > error: failed to load '~/src/tests/libmylib.dyld': Execution was 
> > interrupted, reason: breakpoint site 3.
> > The process has been returned to the state before execution.
> >
> > The error is from ClangUserExpression->Evaluate(). I suppose that 
> > breakpoint site is internal (I only have placed one breakpoint site, in 
> > main()). How can I know what is going on?
> >
> > Regards,
> >
> >   Filipe
> >
> > On Tue, Aug 2, 2011 at 11:07, Filipe Cabecinhas <[email protected]> 
> > wrote:
> > Hi,
> >
> > Here are two small fixed:
> >
> >  - Fixed ifdeffed code that only compiles when debugging with the 
> > DEBUG_STACK_FRAMES flag.
> >  - Makes CommandObjectThreadStepWithTypeAndScope.Execute() behave like what 
> > was described in the mailing list: If there is no selected thread, select 
> > the first one (index 0).
> >
> > Regards,nbsp; Filipe
> >
> >
> > <fix-ifdeffed-code-stackframelist.patch><get-first-thread-if-no-selected-thread.patch><ProcessLoadError.patch>_______________________________________________
> > lldb-dev mailing list
> > [email protected]
> > http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev
> 
> 
> _______________________________________________
> lldb-dev mailing list
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