From mboxrd@z Thu Jan 1 00:00:00 1970 From: tromey@redhat.com (Tom Tromey) Date: Tue, 26 Apr 2011 12:47:28 -0600 Subject: [ltt-dev] gdb-7.2 can't build with lttng-ust-0.12 In-Reply-To: <1865303E0DED764181A9D882DEF65FB6931C75A5AE@shsmsx502.ccr.corp.intel.com> (Dexuan Cui's message of "Tue, 26 Apr 2011 09:49:48 +0800") References: <1865303E0DED764181A9D882DEF65FB6931C75A5AA@shsmsx502.ccr.corp.intel.com> <1865303E0DED764181A9D882DEF65FB6931C75A5AE@shsmsx502.ccr.corp.intel.com> Message-ID: >>>>> "Dexuan" == Cui, Dexuan writes: Mathieu> Also, we should reopen the discussion on the way the UST Markers Mathieu> collect the registers for GDB, because the current way involves a Mathieu> _lot_ of ugly assembly code. It should be possible to only use a Mathieu> volatile inline asm to specify input constraints on the target marker Mathieu> parameters, and keep the instruction pointer address that corresponds Mathieu> to this inline asm in a section known by gdb (so gdb could use the Mathieu> drawf info to fetch data from registers/memory). If you can ensure Mathieu> that this would fit gdb's requirements, I could clean up the marker Mathieu> code and we could resync the APIs together. We could also provide Mathieu> this for UST Tracepoints in the same go, with pretty much the same Mathieu> interface as we'd use for UST Markers. I am aware that this would Mathieu> require change on the GDB side, but I think it's better to Mathieu> synchronise our effort rather than to shoot at different targets. I am not totally clear on the proposal here. If this means reusing the stuff, then there are gdb patches already submitted to fully support that; and updating the existing code to also use it should not be very difficult. See gdb-patches from the last month or two. If instead you mean something else, it would be useful to have more information. From your description it sounds like this may be a different design from SDT v3; but note that SDT v2 tried to use DWARF to access the parameters and ran into various problems. I can get details on the failure modes if this is what you intend. Dexuan> Unluckily I'm pretty new to gdb and know few about this now. Dexuan> Let me Cc the gdb mailing list for more thoughts(hope this cross-posting Dexuan> wouldn't bother people). Cross-posting in cases like this is fine, even preferable. I don't know anything about the gdbserver bits here. It seems to me that it would be reasonable to have gdbserver compile against various versions of UST. Tom