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+[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]]
+
+[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
+id="license" text="Permission is granted to copy, distribute and/or modify this
+document under the terms of the GNU Free Documentation License, Version 1.2 or
+any later version published by the Free Software Foundation; with no Invariant
+Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
+is included in the section entitled [[GNU Free Documentation
+License|/fdl]]."]]"""]]
+
+[[!toc]]
+
+
+# IRC, freenode, #hurd, 2013-06-23
+
+    <hacklu> braunr: sorry for the late reply. Honestly to say, the school
+      works had taken most of my time these days. I haven't got any
+      siginificant progress now. I am trying to write a little debugger demo on
+      Hurd.
+    <hacklu> braunr: things goes more hard than I think, these are some
+      differences between ptrace() on Hurd and Linux. I am trying to  solve
+      this.
+
+
+# IRC, freenode, #hurd, 2013-06-24
+
+    <hacklu> this is my weekly report
+      http://hacklu.com/blog/gsoc-weekly-report1-117/. 
+    <hacklu> and I have two main questions when I read the gdb source code. 
+    <hacklu> 1/What is the S_exception_raise_request()? 2/what is the role of
+      ptrace in gdb port on Hurd?
+    <youpi> hacklu: where did you see S_exception_raise_request?
+    <hacklu> in gdb/gnu-nat.c
+    <youpi> ah, in gdb
+    <hacklu> yeah. and I have read the <The hurd hacking guide>. is says the S_
+      start means server stub. 
+    <youpi> yes
+    <youpi> what happens is that gnu_wait keeps calling mach_msg
+    <youpi> to get a message
+    <youpi> then it passes that message to the various stubs servers
+    <youpi> see just below, it calls exc_server, among others
+    <youpi> and that's exc_server which ends up calling
+      S_exception_raise_request, if the message is an exception_raise request
+    <youpi> exc_server is a mere multiplexer, actually
+    <tschwinge> S_exception_raise_request is the implementation of the request
+      part (so one half of a typical RPC) of the Mach exception interface.
+    <tschwinge> See gdb/exc_request.defs in GDB and include/mach/exc.defs in
+      Mach.
+    <hacklu> youpi: how gnu_wait pass one message to exc_server?  in which
+      function?
+    <youpi> in gnu_wait()
+    <youpi> && !exc_server (&msg.hdr, &reply.hdr)
+    <hacklu> oh, I see this. 
+    <hacklu> firstly I think it is a type check simply.
+    <youpi> see the comment: "handle what we got"
+    <tschwinge> The Hurd's proc server also is involved in the exception
+      passing protocol (see its source code).
+    <hacklu> tschwinge: I will check the source code later. is the exception
+      take place in this way: 1. the inferior call ptrace(TRACE_ME). 2.the gdb
+      call task_set_exception_port. 3. mach send a notification to the
+      exception port set before. 4. gdb take some action.
+    <tschwinge> hacklu: Yes, that's it, roughly.  The idea is that GDB replaces
+      a process' standard exception port, and replaces it "with itself", so
+      that when the process that is debugged receives and exception (by Mach
+      sending a exception_raise RPC), GDB can then catch that and act
+      accordingly.
+    <tschwinge> hacklu: As for your other questions, about ptrace: As you can
+      see in [glibc]/sysdeps/mach/hurd/ptrace.c, ptrace on Hurd is simply a
+      wrapper around vm_read/write and more interfaces.
+    <tschwinge> hacklu: As the GDB port for Hurd is specific to Hurd by
+      definition, you can also directly use these calls in GDB for Hurd.
+    <tschwinge> ..., as it is currently done.
+    <hacklu> and in detail, the part 3 mach send a notification to the
+      excetption port is like this: gnu_wait get the message in mach_msg, and
+      then pass it to exc_serer by exc_server(),then exc_server call
+      S_exception_raise_request()? ?
+    <hacklu> tschwinge: yeah, I have see the ptrace.c. I was wonder about
+      nobody use ptrace in Hurd except TRACEME...
+    <tschwinge> hacklu: Right about »and in detail, [...]«.
+    <tschwinge> hacklu: It would be very good (and required for your
+      understanding anyway), if you could write up a list of things that
+      happens when a process (both under the control of GDB as well as without
+      GDB) is sent an exception (due to a breakpoint instruction, for example).
+    <tschwinge> Let me look something up.
+    <hacklu> tschwinge: what's the function of exc_server? if I can get the
+      notification in mach_msg().
+    <youpi> to multiplex the message
+    <youpi> i.e. decoding it, etc. up to calling the S_ function with the
+      proper parameters
+    <youpi> exc_server being automatically generated, that saves a lot of code
+    <tschwinge> That is generated by MIG from the gdb/exc_request.defs file.
+    <tschwinge> You'll find the generated file in the GDB build directory.
+    <hacklu> I have wrote down the filenames. after this I will check that.
+    <tschwinge> hacklu: I suggest you also have a look at the Mach 3 Kernel
+      Principles book,
+      <http://www.gnu.org/software/hurd/microkernel/mach/documentation.html>.
+    <tschwinge> This also has some explanation of the thread/task's exception
+      mechanism.
+    <tschwinge> And of course, explains the RPC mechanism, which the exception
+      mechanism is built upon.
+    <tschwinge> And then, really make a step-by-step list of what happens; this
+      should help to better visualize what's going on.
+    <hacklu> ok. later I will update this list on my blog.
+    <tschwinge> hacklu: I cannot tell off-hand why GDB on Hurd is using
+      ptrace(PTRACE_TRACEME) instead of doing these calls manually.  I will
+      have to look that up, too.
+    <hacklu> tschwinge: thanks. 
+    <tschwinge> hacklu: Anyway -- you're asking sensible questions, so it seems
+      you're making progress/are on track.  :-)
+    <hacklu> tschwinge: there is something harder than I had thought, I haven't
+      got any meaningful progress. sorry for this.
+    <tschwinge> hacklu: That is fine, and was expected.  :-)  (Also, you're
+      still busy with university.)
+    <hacklu> I will show more time and enthusiasm on this.
+    <tschwinge> hacklu: Oh, and one thing that may be confusing: as you may
+      have noticed, the names of the same RPC functions are sometimes slightly
+      different if different *.defs files.  What is important is the subsystem
+      number, such as 2400 in [GDB]/gdb/exc_request.defs (and then incremented
+      per each routine/simpleroutine/skip directive).
+    <tschwinge> hacklu: Just for completeness, [hurd]/hurd/subsystems has a
+      list of RPC subsystems we're using.
+    <tschwinge> And the name given to routine 2400, for example, is just a
+      "friendly name" that is then used locally in the code where the *.defs
+      file has been processed by MIG.
+    <tschwinge> What a clumsy explanation of mine.  But you'll get the idea, I
+      think.  ;-)
+    <tschwinge> hacklu: And don't worry about your progress -- you're making a
+      lot of progress already (even if it doesn't look like it, because you're
+      not writing code), but the time spent on understanding these complex
+      issues (such as the RPC mechanism) definitely counts as progress, too.
+    <hacklu> tschwinge: not clearly to got it as I am not sensitive with the
+      MIG's grammer. But I know, the exc is the routine 2400's alias name?
+    <tschwinge> hacklu: I'd like to have you spend enough time to understand
+      these fundamental concepts now, and then switch to "hacking mode" (write
+      code) later, instead of now writing code but not understanding the
+      concepts behind it.
+    <hacklu> I have wrote a bit code to validate my understanding when I read
+      the soruce code. But the code not run.  http://pastebin.com/r3wC5hUp
+    <tschwinge> The subsystem directive [...].  As well, let me just point you
+      to the documentation:
+      <http://www.gnu.org/software/hurd/microkernel/mach/mig/documentation.html>,
+      MIG - THE MACH INTERFACE GENERATOR, chapter 2.1 Subsystem identification.
+    <tschwinge> hacklu: Yes, writing such code for testing also is a good
+      approach.  I will have to look at that in more detail, too.
+    * tschwinge guesses hacklu is probably laughing when seeing the years these
+        documents were written in (1989, etc.).  ;-)
+    <hacklu> mach_msg make no sense in my code, and the process just hang. kill
+      -9 can't stop is either.
+    <braunr> hacklu: do you understand why kill -KILL might not work now ?
+    <hacklu> braunr: no, but I found I can use gdb to attach to that process,
+      then quit in gdb, the process quit too.
+    <hacklu> maybe that process was waiting a resume.
+    <braunr> something like that yes
+    <braunr> iirc it's related to a small design choice in the proc server
+    <braunr> something that put processes in an uninterruptible state when
+      being debugged
+    <hacklu> iirc ? 
+    <braunr> if i recall cl=orrectly
+    <braunr> correctly*
+    <hacklu> like D status in linux? 
+    <braunr> or T
+    <braunr> there has been a lot of improvements regarding signal handling in
+      linux over time so it's not really comparable now
+    <braunr> but that's the idea
+    <hacklu> in ps, i see the process STAT is THumx
+    <braunr> did you see that every process on the hurd has at least two
+      threads ?
+    <hacklu> no, but I have see that in hurd, the exception handler can't live
+      in the same context with the victim. so there must be at least two
+      threads. I think
+    <braunr> hacklu: yes
+    <braunr> that thread also handles regular signals
+    <braunr> in addition to mach exceptions
+    <braunr> (there are two levels of multiplexing in servers, first locating
+      the subsystem, then the server function)
+    <braunr> hacklu: if what i wrote is confusing, don't hesitate to ask for
+      clarifications (i really don't intend to make things confusing)
+    <hacklu> braunr: I don't know what you say about the "multiplexing in
+      servers". For instance, is it means how to pass message from  mach_msg to
+      exc_server in gnu_wait()?
+    <braunr> hacklu: i said that the "message thread" handles both mach
+      exceptions and unix signals
+    <braunr> hacklu: these are two different interfaces (and in mach terms,
+      subsystems)
+    <braunr> hacklu: see hurd/msg.defs for the msg interface (which handles
+      unix signals)
+    <braunr> hacklu: to handle multiple interfaces in the same thread, servers
+      need to first find the right subsystem
+    <braunr> this is done by subsequently calling all demux functions until one
+      returns true
+    <braunr> (finding the right server function is done by these demux
+      functions)
+    <braunr> hacklu: see hurd/msgportdemux.c in glibc to see how it's done
+      there
+    <braunr> it's short actually, i'll past it here :
+    <braunr>   return (_S_exc_server (inp, outp) ||
+    <braunr>           _S_msg_server (inp, outp));
+    <braunr> hacklu: did that help ?
+    <hacklu> braunr: a bit more confusing. one "message thread" handles
+      exceptions and signals, means the message thread need to recive message
+      from two port. then pass the message to the right server which handle the
+      message. the server also should pick the right subsystem from a lot of
+      subsystems to handle the msg. is this ? 
+    <braunr> the message thread is a server thread
+    <braunr> (which means every normal process is actually also a server,
+      receiving exceptions and signals)
+    <braunr> there may be only two ports, or more, it doesn't matter much, the
+      port set abstraction takes care of that
+    <hacklu> so the message thread directly pass the msg to the right
+      subsystem?
+    <braunr> not directly as you can see
+    <braunr> it tries them all until one is able to handle the incoming message
+    <braunr> i'm not sure it will help you with gdb, but it's important to
+      understand for a better general understanding of the system
+    <braunr> ugly sentence
+    <hacklu> ah, I see. like this in gnu-nat.c  if(!notify_server(&msg.hdr,
+      &reply.hdr) && !exc_server(&msg.hdr...) 
+    <braunr> yes
+    <hacklu> the thread just ask one by one.
+    <braunr> be careful about the wording
+    <braunr> the thread doesn't "send requests"
+    <braunr> it runs functions
+    <braunr> (one might be tempted to think there are other worker threads
+      waiting for a "main thread" to handle demultiplexing messages)
+    <hacklu> I got it.
+    <hacklu> the notify_server function is just run in the same context in
+      "message thread",and there is no RPC here. 
+    <braunr> yes
+    <hacklu> and the notify_server code is generater by mig automatically.
+    <braunr> yes
+
+
+# IRC, freenode, #hurd, 2013-06-29
+
+[[!tag open_issue_documentation]]
+
+    <hacklu> I just failed to build the demo on
+      this. http://walfield.org/pub/people/neal/papers/hurd-misc/ipc-hello.c
+    <hacklu> or, example in machsys.doc called simp_ipc.c
+    <pinotree> we don't use cthreads anymore, but pthreads
+    <hacklu> pinotree: em.. and I also failed to find the <servers/env_mgr.h>
+      in example of <A programmer's guide to MACH system call>
+    <pinotree> that i don't know
+    <hacklu> maybe the code in that book out-of-date
+    <teythoon> hacklu: mig and mach ipc documentation is quite dated
+      unfortunately, and so are many examples floating around the net
+
+    <hacklu> btw, I have one more question. when I read <Mach 3 kernel
+      interface>. I find this state: When an exception occurs in a thread, the
+      thread sends an exception message to
+    <hacklu> its exception port, blocking in the kernel waiting for the receipt
+      of a reply. It is
+    <hacklu> assumed that some task is listening to this
+    <hacklu> port, using the  exc_serverfunction to decode the messages and
+      then call the
+    <hacklu> linked in  catch_exception_raise. It is the job of
+      catch_exception_raiseto handle the exception and decide the course of
+      action for thread.
+    <hacklu> that says, it assumed another task to recieve the msg send to one
+      thread's exception port. why another task? 
+    <hacklu> I remmebered, there are at least two threads in one task, one is
+      handle the exception stuffs.
+    <braunr> there are various reasons
+    <braunr> first is, the thread causing the exception is usually not waiting
+      for a message
+    <braunr> next, it probably doesn't have all the info needed to resolve the
+      exception
+    <braunr> (depending on the system design)
+    <braunr> and yes, the second thread in every hurd process is the msg
+      thread, handling both mach exceptions and hurd signals
+    <hacklu> but in this state, I can't find any thing with the so called msg
+      thread
+    <braunr> ?
+    <hacklu> if exist a task to do the work, why we need this thread?
+    <braunr> this thread is the "task"
+    <hacklu> ?
+    <braunr> the msg thread is the thread handling exceptions for the other
+      threads in one task
+    <braunr> wording is important here
+    <braunr> a task is a collection of resources
+    <braunr> so i'm only talking about threads really
+    <braunr> 14:11 < hacklu> assumed that some task is listening to this
+    <braunr> this is wrong
+    <braunr> a task can't listen
+    <braunr> only a thread can
+    <hacklu> in you words, the two thread is in the same task?
+    <braunr> yes
+    <braunr> 14:32 < braunr> and yes, the second thread in every hurd process
+      is the msg thread, handling both mach exceptions and hurd signals
+    <braunr> process == task here
+    <hacklu> yeah, I always think the two thread stay in one task. but I found
+      that state in <mach 3 kernel interface>. so I confuzed
+    <hacklu> s/confuzed/confused
+    <braunr> statement you mean
+    <hacklu> if two thread stay in the same task. and the main thread throw a
+      exception, the other thread to handle it?
+    <braunr> depends on how it's configured
+    <braunr> the thread receiving the exceptions might not be in the same task
+      at all
+    <braunr> on the hurd, only the second thread of a task receives exception
+    <braunr> s
+    <hacklu> I just wonder how can the second thread catch the exception from
+      its containning task
+    <braunr> forget about tasks
+    <braunr> tasks are resource containers
+    <braunr> they don't generate or catch exceptions
+    <braunr> only threads do
+    <braunr> for each thread, there is an exception port
+    <braunr> that is, one receive right, and potentially many send rights
+    <braunr> the kernel uses a send right to send exceptions
+    <braunr> the msg thread waits for messages on the receive right
+    <braunr> that's all
+    <hacklu> ok. if I divide zero in main thread, the kernel will send a msg to
+      the main thread's exception port. and then, the second thread(in the same
+      task) is waiting on that port. so he get the msg. is it right?
+    <braunr> don't focus on main versus msg thread
+    <braunr> it applies to all other threads
+    <braunr> as well
+    <braunr> otherwise, you're right
+    <hacklu> ok, just s/main/first
+    <braunr> no
+    <braunr> main *and* all others except msg
+    <hacklu> main *and* all others except msg ?
+    <braunr> the msg thread gets exception messages for all other threads in
+      its task
+    <braunr> (at least, that's how the hurd configures things)
+    <hacklu> got it.
+    <hacklu> if the msg thread throw exception either, who server for himself?
+    <braunr> i'm not sure but i guess it's simply forbidden
+    <hacklu> i used gdb to attach a little progrom which just contains a divide
+      zero. and I only found the msg thread is in the glibc.  
+    <braunr> yes
+    <hacklu> where is the msg thread located in. 
+    <braunr> it's created by glibc
+    <hacklu> is it glibc/hurd/catch-exc.c?
+    <braunr> that's the exception handling code, yes
+    <hacklu> there are some differences between the code and the state in <mach
+      3 system interface>.
+    <braunr> state or statement ?
+    <hacklu> staement
+    <braunr> which one ?
+    <hacklu> http://pastebin.com/ZTBrUAsV
+        When an exception occurs in a thread, the thread sends an exception
+          message to
+        its exception port, blocking in the kernel waiting for the receipt of a
+          reply. It is
+        assumed that some task is listening (most likely with mach_msg_server)
+          to this
+        port, using the  exc_serverfunction to decode the messages and then
+          call the
+        linked in  catch_exception_raise. It is the job of
+          catch_exception_raiseto handle the exception and decide the course of
+          action for  thread. The state of the
+        blocked thread can be examined with thread_get_state.
+    <braunr> what difference ?
+    <hacklu> in the code, I can't find things like exc_server,mach_msg_server
+    <braunr> uh
+    <braunr> ok it's a little tangled
+    <braunr> but not that much
+    <braunr> you found the exception handling code, and now you're looking for
+      what calls it
+    <braunr> simple
+    <braunr> see _hurdsig_fault_init
+    <hacklu> from that statemnet I thought there are another _task_ do the
+      exception things for all of the systems thread before you have told me
+      the task means the msg thread.
+    <braunr> again
+    <braunr> 14:47 < braunr> forget about tasks
+    <braunr> 14:47 < braunr> tasks are resource containers
+    <braunr> 14:47 < braunr> they don't generate or catch exceptions
+    <braunr> 14:47 < braunr> only threads do
+    <hacklu> yeah, I think that document need update.
+    <braunr> no
+    <braunr> it's a common misnomer
+    <braunr> once you're used to mach concepts, the statement is obvious
+    <hacklu> braunr: so I need read more :)
+    <hacklu> _hurdsig_fault_init send exceptions for the signal thread to the
+      proc server?
+    <hacklu> why come about _proc_ server?
+    <braunr> no it gives the proc server a send right for signals
+    <braunr> exceptions are a mach thing, signals are a hurd thing
+    <braunr> the important part is
+    <braunr>   err = __thread_set_special_port (_hurd_msgport_thread,
+    <braunr>                                    THREAD_EXCEPTION_PORT, sigexc);
+    <hacklu> this one set the exception port?
+    <braunr> yes
+    <braunr> hm wait
+    <braunr> actually no, wrong part :)
+    <braunr> this sets the excpetion port for the msg thread (which i will call
+      the signal thread as mentioned in glibc)
+    <hacklu> but the comment above this line, Direct signal thread exceptions
+      to the proc server  means what?
+    <braunr> that the proc server handles exceptions on the signal thread
+    <hacklu> the term signal thread equals the term msg thread?
+    <braunr> yes
+    <hacklu> so, the proc server handles the exceptions throwed by the msg
+      thread?
+    <braunr> looks that way
+    <hacklu> feels a little strange.
+    <braunr> why ?
+    <braunr> this thread isn't supposed to cause exceptions
+    <braunr> if it does, something is deeply wrong, and something must clean
+      that task up
+    <braunr> and the proc server seems to be the most appropriate place from
+      where to do it
+    <hacklu> why need a special server to just work the msg thread? I don't
+      think that thread will throw exception frequentlly
+    <braunr> what does frequency have to do with anything here ?
+    <braunr> ok the appropriate code is _hurdsig_init
+    <braunr> the port for receiving exceptions is _hurd_msgport
+    <braunr> the body of the signal thread is _hurd_msgport_receive
+    <hacklu> aha, in the _hurd_msgport_receive I have finally found the
+      while(1) loop mach_msg_server().
+    <hacklu> so the code is conform with the documents. 
+    <hacklu> braunr: [21:18] <braunr> what does frequency have to do with
+      anything here ? yes, I have totally understood your words now. thank you
+      very much.
+    <braunr> :)
+
+
+# IRC, freenode, #hurd, 2013-07-01
+
+    <hacklu> hi. this is my weekly
+      report. http://hacklu.com/blog/gsoc-weekly-report2-124/ welcome to any
+      comment
+    <hacklu> teythoon: I only get clear about the rpc stuff. seems a lot behind
+      my plan 
+    <youpi> good progress :)
+    <hacklu> I have wrote the details of the exception handle which was asked
+      by tschwing_ last week. Am I all right in my post?
+    <youpi> hacklu: as far as I understand signals, yes :)
+    <hacklu> youpi: thanks for god, I am on the right way finally... :)
+    <hacklu> the mig book says simpleroutine is the one use to implement asyn
+      RPCs which doesn't expect an reply. But I have found a place to pass an
+      reply port to the RPC interface which has been declared as simpleroutine
+    <youpi> hacklu: probably the simpleroutine hardcodes a reply port?
+
+    <youpi> hacklu: about _hurd_internal_post_signal, this is the hairiest part
+      of GNU/Hurd, signal handling
+    <youpi> simply because it's the hairiest part of POSIX :)
+    <youpi> you probably want to just understand that it implements the
+      POSIXity of signal delivering
+    <youpi> i.e. deliver/kill/suspend the process as appropriate
+    <youpi> I don't think you'll need to dive more
+    <hacklu> aha. 
+    <hacklu> it will save a lot of time.
+    <hacklu> it seems like the wait_for_inferior() in gdb. which also has too
+      many lines and too many goto
+    <youpi> hacklu: btw, which simpleroutine were you talking  about ?
+    <hacklu> I forget where it is, I am finding it now.
+    <youpi> which version of gdb are you looking the source of?
+    <youpi> (in mine, wait_for_inferior is only 45 lines long)
+    <hacklu> I dont know how to pick the verison, I just use the git
+      version. maybe I give a wrong name.
+    <youpi> ok
+    <hacklu> youpi:I remembered, my experience comes from here
+      http://www.aosabook.org/en/gdb.html. (All of this activity is managed by
+      wait_for_inferior. Originally this was a simple loop, waiting for the
+      target to stop and then deciding what to do about it, but as ports to
+      various systems needed special handling, it grew to a thousand lines,
+      with goto statements criss-crossing it for poorly understood 
+    <hacklu> reasons.)
+    <hacklu> youpi: the simpleroutine is gdb/gdb/exc_request.defs
+    <youpi> so there is indeed an explicit reply port
+    <hacklu> but simpleroutine is for no-reply use. why use reply port here?
+    <youpi> AIUI, it's simply a way to make the request asynchronous, but still
+      permit an answer
+    <hacklu> ok, I will read the mig book carefully.
+    <braunr> hacklu: as youpi says
+    <braunr> a routine can be broken into two simpleroutines
+    <braunr> that's why some interfaces have interface.defs,
+      interface_request.defs and interface_reply.defs files
+    <braunr> nlightnfotis: in mach terminology, a right *is* a capability
+    <braunr> the only thing mach doesn't easily provide is a way to revoke them
+      individually
+    <nlightnfotis> braunr: Right. And ports are associated with the process
+      server and the kernel right? I mean, from what I have understood, if a
+      process wants to send a signal to another one, it has to do so via the
+      ports to that process held by the process server
+    <nlightnfotis> and it has to establish its identity before doing so, so
+      that it can be checked if it has the right to send to that port.
+    <braunr> yes
+    <nlightnfotis> do process own any ports? or are all their ports associated
+      with the process server?
+    <nlightnfotis> *processes
+    <braunr> mach ports were intended for a lot of different uses
+    <braunr> but in the hurd, they mostly act as object references
+    <braunr> the process owning the receive right (one at most per port)
+      implements the object
+    <braunr> processes owning send rights invoke methods on the object
+    <braunr> use portinfo to find out about the rights in a task
+    <braunr> (process is the unix terminology, task is the mach terminologyà
+    <braunr> )
+    <braunr> i use them almost interchangeably
+    <nlightnfotis> ahh yes, I remember about the last bit. And mach tasks have
+      a 1 to 1 association with user level processes (the ones associated with
+      the process server)
+    <braunr> the proc server is a bit special because it has to know about all
+      processes
+    <braunr> yes
+
+In context of [[open_issues/libpthread/t/fix_have_kernel_resources]]:
+
+    <braunr> hacklu: if you ever find out about either glibc or the proc server
+      creating one receive right for each thread, please let me know
+
+
+# IRC, freenode, #hurd, 2013-07-07
+
+    <hacklu> how fork() goes? 
+    <pinotree> see sysdeps/mach/hurd/fork.c in glibc' sources
+    <hacklu> when the father has two thread( main thread and the signal thead),
+      if the father call fork, then the child inmediatelly call exev() to
+      change the excute file. how many thread in the children?
+    <hacklu> For instance, the new execute file also have two thread. 
+    <hacklu> will the exev() destroyed two threads and then create two new?
+    <hacklu> s/exev()/excv()
+    <hacklu> s/exev()/exec() :)
+
+    <hacklu> what libhurduser-2.13.so does?
+    <hacklu> where can I find this source?
+    <pinotree> contains all the client stubs for hurd-specific RPCs
+    <pinotree> it is generated and built automatically within the glibc build
+      process
+
+    <hacklu> and what is the "proc" server?
+    <pinotree> what handles in user spaces the processes
+    <hacklu> so if  I call proc_wait_request(),  I will go into the
+      S_proc_wait_reply?
+    <hacklu> thanks, I have found that. 
+
+
+# IRC, freenode, #hurd, 2013-07-08
+
+    <hacklu> hi, this is my weekly
+      report. http://hacklu.com/blog/gsoc-weekly-report3-137/
+    <hacklu> this week I have met a lot of obstacles. And I am quite desired to
+      participate in this meeting.
+    <tschwinge> hacklu: So from your report, the short version is: you've been
+      able to figure out how the things work that you were looking at (good!),
+      and now there are some new open questions that you're working on now.
+    <tschwinge> hacklu: That sounds good.  We can of course try to help with
+      your open questions, if you're stuck figuring them out on your own.
+    <hacklu> tschwinge: the most question is: what is the proc server? why need
+      to call proc_get_reqeust() before the mach_msg()?
+    <hacklu> and Is there exist any specific running sequence between father
+      and child task after fork()? And I found the inferior always call the
+      trace_me() in the same time(the trace me printf always in the same line
+      of the output log). which I have post in my report. 
+    <tschwinge> hacklu: The fork man-page can provide a high-level answer to
+      your Q3: »The child process is created with a single thread—the one that
+      called fork().  The entire virtual address space of the parent is
+      replicated in the child, including the states of mutexes, condition
+      variables, and other pthreads objects [...]«
+    <tschwinge> hacklu: What happens in GNU Hurd is that the signal thread is
+      also "cloned" (additionally to the thread which called fork), but then it
+      (the signal thread) is re-started from the beginning.  (So this is very
+      much equivalent to creating a new signal thread.)
+    <tschwinge> hacklu: Then, upon exec, a new memory image is created/loaded,
+      replacing the previous one.  [glibc]/sysdeps/mach/hurd/execve.c.  What
+      actually happens with the existing thread (in particular, the signal
+      thread) I don't know off-hand.  Then answer is probably found in
+      [glibc]/hurd/hurdexec.c -- and perhaps some code of the exec server
+      ([hurd]/exec/).
+    <hacklu> I have checked the status of my regiter mail to FSF. it says it
+      had arrived in USA. 
+    <tschwinge> hacklu: OK, good.
+    <tschwinge> hacklu: This is some basic information about the observer_*
+      functions is GDB:
+      http://sourceware.org/gdb/current/onlinedocs/gdbint/Algorithms.html#index-notifications-about-changes-in-internals-57
+      »3.10 Observing changes in gdb internals«.
+    <hacklu> tschwinge: not too clear. I will think this latter. and what is
+      the proc server?
+    <teythoon> hacklu: /hurd/proc, maps unix processes to mach threads afaiui
+    <hacklu> teythoon: question is, the mach_msg() will never return unless I
+      called proc_wait_request() first.
+    <teythoon> hacklu: sorry, I've no idea ;)
+    <hacklu> teythoon: :)
+    <tschwinge> hacklu: I will have to look into that myself, too; don't know
+      the answer off-hand.
+    <tschwinge> hacklu: In your blog you write proc_get_request -- but such a
+      functions doesn't seems to exist?
+    <hacklu> tschwinge: s/proc_get_request/proc_wait_request  called in
+      gun_wait() [gnu-nat.c]
+    <tschwinge> hacklu: Perhaps the wait man-page's description of WUNTRACED
+      gives a clue: »also return if a child has stopped [...]«.  But it also to
+      me is not yet clear, how this relates to the mach_mag call, and how the
+      proc server exactly is involved in it.
+    <tschwinge> I'm reading various source code files.
+    <tschwinge> At least, I don't undestand why it is required for an exception
+      to be forwarded.
+    <hacklu> if I need to read the proc server source code?
+    <tschwinge> I can see how it to become relevant for the case that GDB has
+      to be informed that the debugee has exited normally.
+    <tschwinge> hacklu: Yeah, probably you should spend some time with that, as
+      it will likely help to get a clearer picture of the situation, and is
+      relevant for other interactions in GDB, too.
+    <tschwinge> hacklu: By the way, if you find that pieces of the GDB source
+      code (especially the Hurd files of it) are insufficiently documented,
+      it's a very good idea, once you have figured out something, to add more
+      source code comments to the existing code.  Or writed these down
+      separately, if that is easier.
+    <hacklu> which is the proc server? hurd/exec ?
+    <hacklu> that ok, I already comment things on my notes. 
+    <tschwinge> hacklu: [Hurd]/proc/
+    <tschwinge> hacklu: And [Hurd]/hurd/process*.defs
+    <hacklu> got it
+    <tschwinge> hacklu: I'll have to experiment a bit with your HDebugger
+      example, but I'm out of time right now, sorry.  Will continue later.
+    <hacklu> tschwinge: yep, the HDebugger has a problem, if you put the
+      sleep() after the printf in the just_print(), thing will hang. 
+    <hacklu> tschwinge: and I am a little curious about how do you find my
+      code? I dont't remember I have mentioned that :)
+    <hacklu> tschwinge: I have post my gihub link in the last week report, I
+      found that.
+    <tschwinge> hacklu: That's how I found it, yes.
+    <hacklu> tschwinge: :)
diff --git a/community/gsoc/2013/nlightnfotis.mdwn b/community/gsoc/2013/nlightnfotis.mdwn
new file mode 100644
index 00000000..43f9b14c
--- /dev/null
+++ b/community/gsoc/2013/nlightnfotis.mdwn
@@ -0,0 +1,450 @@
+[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]]
+
+[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
+id="license" text="Permission is granted to copy, distribute and/or modify this
+document under the terms of the GNU Free Documentation License, Version 1.2 or
+any later version published by the Free Software Foundation; with no Invariant
+Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
+is included in the section entitled [[GNU Free Documentation
+License|/fdl]]."]]"""]]
+
+[[!toc]]
+
+
+# IRC, freenode, #hurd, 2013-06-29
+
+    <teythoon> so, how is your golang port going?
+    <nlightnfotis> I just started working on it. I had been reading
+      documentation so far. Maybe over reading as people told me when I asked
+      for their feedback
+    <nlightnfotis> but I will report on what I have done (technically tomorrow,
+      and post it in the mailing list too.
+
+    <nlightnfotis> Hey guys, what could possibly cause the following error
+      message when executing a program in the Hurd? "./dumper: Could not open
+      note: (system server) error with unknown subsystem"
+    <nlightnfotis> My program is one that opens a file and dumps it into stdout
+    <nlightnfotis> pinotree: the code I am using is the one present here
+      http://www.gnu.org/software/hurd/hacking-guide/hhg.html under paragraph
+      6.1
+    <nlightnfotis> I investigated it a bit but can not find a lead. I seem to
+      have all the rights to open the file that I want to dump to stdout
+    <pinotree> what if you reset errno to 0 just after all the declarations in
+      main, before the instructions?
+    <nlightnfotis> will check this out and get back to you.
+    <pinotree> sure :)
+    <nlightnfotis> pinotree: Now it suggests that it can't get the number of
+      readable files, which the source suggests that is normal behavior.
+      Thanks for your assistance.
+
+
+# IRC, freenode, #hurd, 2013-07-01
+
+    <nlightnfotis> youpi: from my part I can report that I have started working
+      with the code, and doing as Thomas suggested. I was about to write my
+      report yesterday, but I am facing some build errors on the HURD, which I
+      would like to investigate further before I write my report.
+    <nlightnfotis> that's why I decided to write it later in the day.
+    <youpi> I don't think you have to wait
+    <youpi> you can simply write in your report that you are having build
+      errors
+    <nlightnfotis> ok. I will have it written and delivered later in the day.
+    <nlightnfotis> braunr: that's cool. I think my reading has paid for
+      itself. And you may be pleased to know that I have gotten my hands dirty
+      with the code. I was about to write report yesterday, but some build
+      errors with the gcc (that I am investigating atm) are holding me
+      off. Will have that written later in the day.
+    <braunr> don't hesitate to ask help about build errors
+    <braunr> don't wait too much
+    <braunr> you need to progress on what matters, and not be blocked by
+      secondary problems
+    <nlightnfotis> I will see myself asking for help rather sooner than later,
+      but I would like to investigate it myself, and attempt to solve the
+      issues that occur to me before resort to bugging you guys.
+    <braunr> sure
+    <braunr> just not too long
+    <braunr> too long being a day or so
+    <nlightnfotis> these were my build_results on the hurd
+    <nlightnfotis> they were linker errors
+    <nlightnfotis>
+      https://gist.github.com/NlightNFotis/5896188#file-build_results
+    <nlightnfotis> I am trying to build gcc on a linux 32 bit environment. It
+      also has some issues but not linker errors
+    <nlightnfotis> will resolve them to see if the linker errors are
+      reproducible on linux
+    <braunr> oh, lex stuff
+    <braunr> should be easy enough
+
+
+# IRC, freenode, #hurd, 2013-07-05
+
+    <nlightnfotis> I have not made much progress, but I see myself working with
+      it.
+    <nlightnfotis> I have managed to build gcc go on Linux
+    <nlightnfotis> but Hurd seems to have some issues
+    <nlightnfotis> it seems to randomly crash
+    <teythoon> the build process?
+    <nlightnfotis> not quite randomly it seems to be though
+    <nlightnfotis> yeah
+    <nlightnfotis> I have noticed that there is a pattern
+    <nlightnfotis> it does crash after some time
+    <teythoon> ^^
+    <nlightnfotis> but it doesn't crash at specific files
+    <braunr> define crash
+    <nlightnfotis> at some times it may crash during compiling insn-emit.c
+    <braunr> (hello guys)
+    <teythoon> hi braunr :)
+    <nlightnfotis> braunr: hey there! It does seem to keep on compiling this
+      file for a very long time (I have let it do so for 10, 20, 30 minutes)
+      but the result is the same
+    <nlightnfotis> and it does so for different files for different build
+      options
+    <braunr> ok so it doesn't crash
+    <braunr> it just doesn't complete
+    <braunr> is the virtual machine eating 100% cpu during that time ?
+    <nlightnfotis> I can still type at the terminal, but I can't send a term
+      signal
+    <nlightnfotis> I can report that QEMU does hold 100% of one core at that
+      time, (like it keeps processing) but there is no output on the terminal
+    <braunr> ok
+    <nlightnfotis> of course I can type at the terminal
+    <nlightnfotis> but nothing happens
+    <braunr> any idea of the size of the files involved ?
+    <nlightnfotis> I am checking it out right now
+    <nlightnfotis> before this goes any further, let me report on my
+      investigation
+    <braunr> i expect that to be our classic writeback thread storm issue
+    <nlightnfotis> initially, I thought it might be that it run out of memory
+    <nlightnfotis> even though I know that compilation is not memory intensive,
+      rather, cpu intensive
+    <nlightnfotis> anyway I increased the size of ram available to the vm
+    <nlightnfotis> from 1024 mb to 1536
+    <nlightnfotis> that didn't seem to have any effect. The "crash" still
+      happens at the same time, at the same files
+    <braunr> use freeze
+    <braunr> not crash
+    <braunr> crash is very misleading here
+    <nlightnfotis> freeze it is then.
+    <nlightnfotis> anyway
+    <nlightnfotis> then it striked me that it might be that the hard disk size
+      (3gb) might be too small (considering the gcc git repo is 1gb+)
+    <nlightnfotis> so I resized the qemu image to 8gb of hdd size
+    <nlightnfotis> the new size is acknowledged by the vm
+    <pinotree> for gcc in debug mode? might still not be enough
+    <nlightnfotis> but still it has no effect - it seems to follow its freezing
+      patterns
+    <pinotree> giving your work, i'd have not less than 15-20
+    <braunr> i'd use 32
+    <pinotree> *given
+    <braunr> but that's because i like power of twos
+    <nlightnfotis> pinotree: thanks for the advice. Right now I was gonna
+      increase the swap size
+    <nlightnfotis> according to vmstat in the hurd
+    <nlightnfotis> swap size is 173 mb
+    <nlightnfotis> don't know if it does have an impact
+    <braunr> it may but before rushing
+    <braunr> if you need swap, you're doomed anyway
+    <braunr> consider swap highly unreliable on the hurd
+    <braunr> please show the output of df -h on the file system you're using to
+      build
+    <braunr> ideally, i'd recommend using separate / and /home file systems
+    <braunr> it really improves reliability
+    <nlightnfotis> I don't think it swaps to be honest; however that's
+      something that my mentor thomas had suggested (increasing swap size) so I
+      am gonna try it at some time.
+    <pinotree> or have a separate file system in a subdi and work on it
+    <braunr> yes, /home or whatever suits you
+    <braunr> just not /
+    <nlightnfotis> braunr: pinotree: thanks both for your advice. Will do now,
+      and report on the results.
+    <braunr> that's not all
+    <braunr> 11:17 < braunr> please show the output of df -h on the file system
+      you're using to build
+    <nlightnfotis> braunr: I am on it. Oh and btw, everytime I am forced to
+      close the vm (due to the freezes) when I restart it ext2 reports that the
+      file system was not cleanly unmounted and does some repair to some
+      files. I am trying to find an explanation for that, but I can think of
+      many things
+    <braunr> well obviously
+    <pinotree> ext2 has no journaling
+    <braunr> the file system was not cleanly unmounted since you restarted it
+      with a cold reset
+    <nlightnfotis> braunr: df -h comes out with this: "df: cannot read table of
+      mounted file systems"
+    <pinotree> also, even if you manage to always shut down correctly, when
+      fsck runs because of the maximum mount count it'd find errors anyway (so
+      we have some bug)
+    <braunr> nlightnfotis: df -h /path/to/build/dir
+    <braunr> pinotree: not really bugs but it could be cleaned up
+    <nlightnfotis> filesystem: - Size 2.8G Used 2.8G Avail 0 Use% 100% Mounted
+      on /
+    <nlightnfotis> wow
+    <braunr> nlightnfotis: see
+    <nlightnfotis> that seems to explain many things
+    <teythoon> ^^
+    <nlightnfotis> thanks for that braunr!
+    <braunr> you resized the disk, but not the partition and the file system
+    <pinotree> braunr: well, if something in ext2 (or its libs) leaves issues
+      in the fs, i'd call that a bug :>
+    <nlightnfotis> yeah, that was utterly stupid of me
+    <braunr> pinotree: they're not issues
+    <braunr> nlightnfotis: be careful, mach needs a reboot every time you
+      change a partition table
+    <teythoon> nlightnfotis: important thing is that you found the issue :)
+    <braunr> then only, you can use resize2fs
+    <teythoon> braunr: weird, I thought mach nowadays can reload the partition
+      tables?
+    <teythoon> braunr: doesn't d-i need that?
+    <braunr> maybe a recent change i forgot
+    <braunr> or maybe fdisk still reports the error although it's fine
+    <braunr> in doubt, rebooting is still safe :p
+    <teythoon> or maybe youpi hacked it into d-is gnumach
+    <braunr> i doubt it would be there for the installer only :)
+    <braunr> if it's there, it's there
+    <braunr> i just don't know it
+    <nlightnfotis> braunr: teythoon: and everyone else that helped me. Thanks
+      you all guys. This was something that was driving me crazy. Will do all
+      that you suggested and report back on my status
+
+
+# IRC, freenode, #hurd, 2013-07-08
+
+    <nlightnfotis> tschwinge, I have managed to overcome most of the obstacles
+      I had initially faced with my project
+    <nlightnfotis> but I still had some build errors, that's why I have not
+      reported yet. Wanna try to see if I can resolve them today, and write my
+      report in the afternoon.
+    <tschwinge> nlightnfotis: So, from a quick look into the IRC backlog, it
+      was a "simple" out of disk space problem?  %-)  That happens.
+    <tschwinge> nlightnfotis: And yes, GCC needs a lot of disk space.
+    <tschwinge> nlightnfotis: What kind of build errors are you seeing now?
+    <nlightnfotis> tschwinge, yeah I felt stupid at the time, but it didn't
+      actually strike me that the file system didn't see the extra space. Also
+      it took me some time to figure out that in order to mount the new
+      partition, I only had to edit /etc/fstab
+    <nlightnfotis> always tried to mount it with the ext2 translator
+    <nlightnfotis> and the translator kept dying
+    <nlightnfotis> but it's all figured out now
+    <nlightnfotis> the latest build errors I am seeing are these
+    <teythoon> nlightnfotis: o_O you used fstab and it worked?
+    <nlightnfotis> yeah
+    <teythoon> nlightnfotis: that's unexpected from my perspective...
+    <nlightnfotis> I only had to add the new partition into fstab
+    <nlightnfotis> teythoon: I can pastebin my fstab if you wanna take a look
+      at it
+    <nlightnfotis> tschwinge: these were my latest build errors
+      https://www.dropbox.com/s/b0pssdnfa22ajbp/build_results
+    <teythoon> nlightnfotis: I'm pretty sure that mount -a isn't done on hurd
+      w/o pinos runsystem.sysv
+    <teythoon> weird
+    <nlightnfotis> tschwinge: I have also tried to build gcc with "make -w"
+      which from what I know supresses the errors that stopped compilation
+    <nlightnfotis> but the weird thing is that gcc nearly took forever to build
+    <teythoon> nlightnfotis: could you do a showtrans /your/mountpoint?
+    <nlightnfotis> teythoon: /hurd/ext2fs /dev/hd0s3
+    <teythoon> nlightnfotis: ok, so you've set a passive translator and an
+      active is started on demand
+    <nlightnfotis> it must be a passive translator
+    <teythoon> nlightnfotis: this is the hurd way of doing things, fstab is
+      unrelated
+    <nlightnfotis> it seems to persist during reboots
+    <teythoon> yes, exactly
+    <nlightnfotis> teythoon: my fstab if you wanna take a look
+      http://pastebin.com/ef94JPhG
+    <nlightnfotis> after I added /dev/hd0s3 to fstab along with its mountpoint,
+      and restarting the hurd, only then I did manage to use that partition
+    <nlightnfotis> before doing so I tried pretty much anything involving
+      mounting the partition and setting the ext2fs translator for it, but it
+      kept dying
+    <nlightnfotis> of course it was a ext2 filesystem
+    <youpi> err, perhaps adding to fstab simply triggered an fsck at reboot?
+    <teythoon> nlightnfotis: might have been that you needed to reboot mach so
+      that it picks up the new partition table
+    <teythoon> youpi: I thought this was fixed, the partition reloading I mean?
+    <youpi> that is needed, yes
+    <youpi> let me check
+    <nlightnfotis> youpi: it could be, though, to be honest, my hurd system
+      does an fsck all the time at boot
+    <teythoon> how do you manage to do that w/o rebooting for d-i?
+    <youpi> (I don't remember whether device busy is detected)
+    <youpi> teythoon: by making all translators go away, iirc
+    <teythoon> nlightnfotis: btw, you have ~/gcc_new as mountpoint in your
+      fstab, pretty sure that this cannot work, the path has to be absolute and
+      no ~ expansion is done
+    <nlightnfotis> tbh it does work, and it's weird
+    <teythoon> nlightnfotis: it works b/c of the passive translator you set,
+      not b/c of the fstab entry
+    <nlightnfotis> teythoon: should I change it?
+    <teythoon> probably, yes
+    <tschwinge> Well, that is probably not used anywhere.
+    <teythoon> tschwinge: not yet but soon ;)
+    <tschwinge> Isn't /etc/fstab only consulted for fsck.
+    <youpi> atm yes
+    <tschwinge> Anyway, it is definitely a very good idea to have a partition
+      separate from the rootfs for doing actual work.
+    <tschwinge> I think I described that in one of the first GSoC coodridation
+      emails.  In the long one.
+    <nlightnfotis> teythoon: Oh it struck me now! Is it because tilde expansion
+      is only happening in bash, but /etc/fstab is read before bash is
+      initialized?
+    <tschwinge> nlightnfotis: Instead of fumbling around with partitioning of
+      disk images, it may be easier in your KVM/QEMU setup to simply add a new
+      disk using -hdb [file] (or similar).
+    <tschwinge> nlightnfotis: Basically, yes.
+    <youpi> nlightnfotis: fstab is not related with bash in any way
+    <nlightnfotis> anyway, it shouldn't matter now, it seems to be working, and
+      I wouldn't like fiddling around with it and messing it up now. I will
+      continue with resolving the gcc issues.
+    <tschwinge> But /etc/fstab has its very own "language" (layout), so tilde
+      expansion will never be done there.
+    <tschwinge> nlightnfotis: df -h ~/gcc_new/
+    <nlightnfotis> tschwinge: size 24G Used: 4.2G Avail 18G
+    <tschwinge> OK, that's fine.
+    <tschwinge> As you can see on
+      <http://darnassus.sceen.net/~hurd-web/open_issues/gcc/#index4h1>, GCC
+      will easily need some GiB.
+    <nlightnfotis> tschwinge: I have some questions about GCC: out of curiosity
+      how much time does it take to compile it on your machine? Because
+      yesterday I tried a -w (suppress warnings) build and it seemed to take
+      forever
+    <nlightnfotis> mind you the vm has 1536 ram available (I have read
+      somewhere that it can utilise such an amount) and the vm is KVM enabled
+    <youpi> without disabling g++, it can easily take hours
+    <tschwinge> nlightnfotis: The build error is unexpected, because I had
+      addressed that issue in a recent patch.  :-)
+    <tschwinge> nlightnfotis: This is wrong: »checking whether setcontext
+      clobbers TLS variables... [...] yes«.  Please check your sources, that
+      they correspond to the current version of the upstream
+      tschwinge/t/hurd/go branch.
+    <tschwinge> nlightnfotis: Quoting from that wiki page: »This takes up
+      around 3.5 GiB, and needs roughly 3.5 h on kepler.SCHWINGE and 15 h on
+      coulomb.SCHWINGE.«  The latter is my Hurd machine.
+    <tschwinge> That's however with Java and Ada enabled, and a full
+      three-stages bootstrap.
+    <youpi> ah, right, there's java & ada too
+    <nlightnfotis> tschwinge: git branch (in the repo): master,
+      *tschwinge/t/hurd/go
+    <youpi> in debian they are built separately
+    <tschwinge> What I asked you to do is configure »--disable-bootstrap
+      --enable-languages=go«.
+    <tschwinge> So that should be a lot quicker.
+    <nlightnfotis> tschwinge: oh yes, everytime I have tried to compile gcc I
+      have done with these configurations
+    <tschwinge> But still a few hours perhaps.
+    <nlightnfotis> that's what I did yesterday too.
+    <tschwinge> OK, good.  :-)
+    <tschwinge> A bootstrap build is a good way to check the just-built GCC for
+      sanity, but we expect that it is fine, as we concentrate on the GCC Go
+      port.
+    <nlightnfotis> the only "extra" configuration yesterday was my "-w" flag to
+      make, because those errors were actually triggered by -Werror
+    <tschwinge> Let me read up what make -w does.  ;-)
+    <nlightnfotis> ah, yes, d/w I have read and understood what the bootstrap
+      build is. Seems like we don't need it atm
+    <nlightnfotis> afaik it suppresses all warnings
+    <pinotree> youpi: gcj no more
+    <nlightnfotis> the way gcc builds, it does convert (some) warnings to
+      errors
+    <tschwinge> Hmm.  -w, --print-directory Print a message containing the
+      working directory before and after other processing.
+    <pinotree> youpi: doko folded gcj and gdc into gcc-4.8 to "workaround"
+      Built-Using
+    <tschwinge> nlightnfotis: Ah, that'S configure --enable-werror or something
+      like that.
+    <youpi> pinotree: right
+    <nlightnfotis> yep, and -w suppresses it
+    <nlightnfotis> (from what I have understood)
+    <tschwinge> nlightnfotis: Are you thinking about make -k?
+    <tschwinge> Yeah, I guess.
+    <nlightnfotis> let me see what -k does
+    <pinotree> youpi: (just to make builds even more lightweight, eh</irony>)
+    <nlightnfotis> yeah, -k should do too, I shall try it
+    <tschwinge> But: if gcc -Werror fails, even with make -k, the build will
+      not be able to come to a successful end, because that one complation
+      artefact that failed will be missing.
+    <nlightnfotis> so I shall try again with -w (supressed warnings)
+    <tschwinge> Configureing with --disable-werror (or similar) will "help" if
+      -Werror is the default, and the build fails due to that.
+    <nlightnfotis> from what I have understood these "errors" are not something
+      critical: it's only that function prototypes for these functions are
+      missing
+    <nlightnfotis> I have seen the code there, and even "default" gcc generated
+      prototypes (from the first usage of the function) should do, so I can't
+      understand why it might be a serious problem if I tell gcc to skip that
+      point
+    <tschwinge> nlightnfotis: Ah, now I see.  You don't mean make -w, but
+      rather gcc -w: »-w  Inhibit all warning messages.«
+    <tschwinge> But really, there shouldn't be such warnings/errors that make
+      the build fail.
+    <nlightnfotis> yeah
+    <tschwinge> nlightnfotis: In your GCC sources directory, what does this
+      tell: git rev-parse HEAD
+    <tschwinge> And, is the checkout clean: git status
+    <tschwinge> The latter will take some time.
+    <nlightnfotis> git status takes an awful amount of time
+    <nlightnfotis> last I checked
+    <nlightnfotis> but git rev-parse HEAD
+    <nlightnfotis> produces this result:
+    <nlightnfotis> 91840dfb3942a8d241cc4f0e573e5a9956011532
+    <tschwinge> OK, that's correct.  So probably some of the checked out files
+      are not in a pristine state?
+    <nlightnfotis> I shall run a git clean and see. If that doesn't work too,
+      maybe I shall reclone the repository?
+    <nlightnfotis> there's nothing foreign to the repo that I have added, only
+      lib gmp, lib mpc and lib mpfr (and they are in their own folders inside
+      my gcc working directory)
+    <tschwinge> nlightnfotis: You shouldn't need to do the latter if you
+      instead run: apt-get build-dep gcc-4.8
+    <nlightnfotis> I remember having done that inside the Hurd, but it always
+      resulted in an error from what I can recall
+    <nlightnfotis> let me check this out
+    <nlightnfotis> yes
+    <tschwinge> nlightnfotis: Whenever you use Git on Hurd, pass the --quiet
+      flag, to avoid the rare but possible corruption issue described on
+      <http://darnassus.sceen.net/~hurd-web/open_issues/git_duplicated_content/>
+      and <http://darnassus.sceen.net/~hurd-web/open_issues/git-core-2/>.
+    <nlightnfotis> tschwinge: Forgive me for that. I will set up an alias
+      immediately.
+    <tschwinge> nlightnfotis: I don't know if an alias is possible, because --
+      I think -- you'll need to do things like: git fetch --quiet
+    <tschwinge> So pass --quiet to subcommands.
+    <nlightnfotis> oh. ok.
+    <tschwinge> nlightnfotis: What you can also do, is shut down your Hurd VM,
+      and mount the disk image on GNU/Linux (mount with offset to get the right
+      partition), and then run a diff -ru against a Git clone done on
+      GNU/Linux, and see whether there are any unexpected differences outside
+      of the .git/ directory.
+    <nlightnfotis> sounds like a plan. I will check this out today then :)
+    <nlightnfotis> tschwinge: if all else fails, then recloning the repo with
+      --quiet passed should work, right?
+    <tschwinge> Yes, that's probably the most straight-forward check to do.
+    <tschwinge> Heh, yes to both these questions.  :-)
+    <tschwinge> nlightnfotis: Oh, you don't even have to re-clone, but rather
+      re-check-out the branch.
+    <nlightnfotis> I was thinking of recloning just to bring the whole
+      repository to a pristine state
+    <tschwinge> So something like (inside the source directory): rm -rf ./*
+      (remove any files, but leave .* in place, in particular the .git/
+      directory), followd by git checkout -f HEAD --quiet
+    <tschwinge> nlightnfotis: But before doing that, please do the diff first,
+      so that we know (hopefully) where the erroneous build results were coming
+      from.
+    <nlightnfotis> considering the Copyright assignment files, I have sent them
+      from day 1 (that is the 20th of June). I have not heard anything about
+      those documents to date (sadly)
+    <nlightnfotis> what's worst is that although I have a reference number to
+      track those documents, their (greek postal office) tracking service sucks
+      so badly, that one day it's offline, the next it suggests it can't find
+      the object in their database, the next it says it is still in the local
+      post office
+    <nlightnfotis> let me check it out now
+    <nlightnfotis> still nothing from their online service
+    <nlightnfotis> let me call them
+    <nlightnfotis> tschwinge: I called the post office regarding the copyright
+      papers. They told me that the same day (the 20th of June) it left from
+      Herakleion, Crete to Athens and the same day it must have left the
+      country heading towards the US. They also told me it takes about 1 week
+      for it to arrive.
+    <tschwinge> nlightnfotis: OK, so probably waiting at the FSF office to be
+      processed.  Let's allow for some more time.  After all, this is not
+      critical for your progress.