[Bug translator/13842] aggressive function merging gives confusing error messages

["jistone at redhat dot com" <sourceware-bugzilla@sourceware.org>]

http://sourceware.org/bugzilla/show_bug.cgi?id=13842

Josh Stone <jistone at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|aggressive cast accessor    |aggressive function merging
                   |function merging gives      |gives confusing error
                   |confusing error messages    |messages

--- Comment #2 from Josh Stone <jistone at redhat dot com> 2012-03-14 01:32:16 UTC ---
(In reply to comment #0)
> Also note that this can also happen with different structures where the field
> accessed is at the same offset in each.

Well, really this can happen with *any* functions that look the same to the
translator, and probably any probe bodies too.  For example:

$ cat pr13842.stp 
global v = $1
function foo() { return 1/0 }
function bar() { return 1/0 }
probe begin { v = v ? foo() : bar() }

$ stap -c true pr13842.stp 0
ERROR: division by 0 near operator '/' at pr13842.stp:3:26
WARNING: Number of errors: 1, skipped probes: 0
WARNING: /usr/bin/staprun exited with status: 1
Pass 5: run failed.  Try again with another '--vp 00001' option.

$ stap -c true pr13842.stp 1
ERROR: division by 0 near operator '/' at pr13842.stp:3:26
WARNING: Number of errors: 1, skipped probes: 0
WARNING: /usr/bin/staprun exited with status: 1
Pass 5: run failed.  Try again with another '--vp 00001' option.

Despite changing the argument, I got the error string pointing to the same
place.  From this I can infer that foo() was collapsed into bar(), confirmed by
inspecting pass2 or pass3 output.

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.