Re: 12.3-RC1 fails to compile perl,tcl86 (ipfw dtrace issue)

On Mon, Nov 22, 2021 at 09:52:38PM +0100, Peter wrote:
> On Mon, Nov 22, 2021 at 10:45:09AM -0500, Mark Johnston wrote:
> ! On Sun, Nov 21, 2021 at 10:46:30PM +0100, Peter wrote:
> ! > ## this seems not have arrived on the list at first send ##
> ! > 
> ! > > dtrace: failed to establish error handler: "/usr/lib/dtrace/ipfw.d",
> ! > > line 106: failed to copy type of 'inp': Conflicting type is already defined
> ! > 
> ! > > That file ipfw.d appears to be new in 12.3, but I'm clueless what
> ! > > the error means (and why it happens only to me).
> ! > 
> ! > 
> ! > I figured out why - I have "device dtraceall" in my kernel. This is
> ! > reproducible: 
> ! > 
> ! > > root@y12y:/ # dtrace -h
> ! > > dtrace: -h requires one or more scripts or enabling options
> ! > > root@y12y:/ # kldload dtraceall
> ! > > root@y12y:/ # dtrace -h
> ! > > dtrace: failed to establish error handler: "/usr/lib/dtrace/ipfw.d", line 106: failed to copy type of 'inp': Conflicting type is already defined
> ! > > root@y12y:/ # kldunload dtraceall
> ! > > root@y12y:/ # dtrace -h
> ! > > dtrace: -h requires one or more scripts or enabling options
> ! > 
> ! > 
> ! > But we do already have a bug (#254483) for this error.
> ! > 
> ! > This bug was closed as duplicate to bug #258763, and the latter one
> ! > was closed as solved with a fix as stated here:
> ! > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=258763#c7
> ! > 
> ! > 
> ! > But the fancy is:
> ! > 
> ! >  1. that fix appears to have missed the releng/12.3 branch by three
> ! >     days, so it is not in the code. But also 
> ! > 
> ! >  2. if applied, (*surprize*) that fix does NOT help!
> ! 
> ! Hmm, that is indeed surprising.  I'm able to reproduce the problem
> ! locally.
> ! 
> ! > More than one thing is wrong here, and bug #254483 is *not* a
> ! > duplicate to #258763.
> ! > 
> ! > The failure does NOT come from code covered by Mark Johnstons fix.
> ! > 
> ! > It comes from a neighboring section where Integers are compared, and
> ! > it fails with a type conflict 8bit vs. 32bit.
> ! > 
> ! > 
> ! > The problem must be within /usr/lib/dtrace/ipfw.d  - and indeed
> ! > it is (irrelevant parts stripped away):
> ! > 
> ! > > typedef struct ipfw_match_info {
> ! > >        struct mbuf     *m;
> ! > > } ipfw_match_info_t;
> ! > > 
> ! > > translator ipfw_match_info_t < struct ip_fw_args *p > {
> ! > >        m =             p->m;
> ! > > };
> ! > 
> ! > This does not work. Within the 'struct mbuf' definition is a
> ! > construct, that looks like this:
> ! > 
> ! > >        uint32_t         m_type:8,      /* type of data in this mbuf */
> ! > >                         m_flags:24;    /* flags; see below */
> ! > 
> ! > And it seems that is somehow the cause for the integer size conflict
> ! > (not implemented?)
> ! 
> ! How did you come to that conclusion?
> 
> Well, that's my trade secret :)
> 
> | Indeed, the problem had to do with handling of bitfield types in libctf.
> | The problem you found is fixed by
> | https://cgit.freebsd.org/src/commit/?id=3cbb4cc200f8a0ad7ed08233425ea54524a21f1c
> | but that change was not merged to 12.  I just merged it to stable/12 and
> | will try to get both libctf changes into 12.3, as both are required for
> | dtrace to work properly while ipfw.ko is loaded.         
> 
> That would be great, but ... I gave that patch a quick try, and
> doesn't yet seem to work, it is now a different error message:
> 
> > dtrace: failed to establish error handler: "/usr/lib/dtrace/ipfw.d", line 106: failed to copy type of 'inp': Invalid type identifier

Hmm.  Just to be clear, this is with both libctf patches applied,
libctf.so reinstalled, and with a pristine ipfw.d?  If so, I'm not able
to reproduce the problem.