Re: Troubles building world on stable/13

From: Mark Millard <marklmi_at_yahoo.com>
Date: Thu, 03 Feb 2022 08:05:42 UTC
On 2022-Feb-2, at 17:51, bob prohaska <fbsd@www.zefox.net> wrote:

> On Wed, Feb 02, 2022 at 04:18:07PM -0800, Mark Millard wrote:
>> On 2022-Feb-2, at 14:32, bob prohaska <fbsd@www.zefox.net> wrote:
>> 
>>> The latest Pi3 single-user -j1 buildworld stopped with clang error 139.
>>> Running the .sh and .cpp files produced an error. The .sh was
>>> re-run under lldb and backtraced.
>> 
>> I'll see if I can find any interesting information based on
>> the "fault address: 0x5" and source code related to the
>> backtrace reporting .

Between the source code and the assembler, I've yet
to see how the value 0x5 ended up as the address
used.

>>> The output is at
>>> http://www.zefox.net/~fbsd/rpi3/clang_trouble/20220202/lldb_session
>>> along with the buildworld log and related files in the same directory.
>> 
>> Your 20220202/readme reports:
>> 
>> QUOTE
>> The first attempt to run  lldb-gtest-all-fe760c.sh  finished with exit
>> code zero.  A subsequent try produced the expected output reported
>> here in lldb_session.
>> END QUOTE
>> 
>> (You had also reported (off list) a recent prior failure where the
>> .sh/.cpp pair did not repeat the failure when you tired it.)
>> 
>> Well:
>> 
>> http://www.zefox.net/~fbsd/rpi3/clang_trouble/20220202/gtest-all-fe760c.o
>> 
>> seems to be a possibly valid compile result to go along with the
>> run (under lldb) that finished normally (exit code zero).
>> 
>> I can not see the dates/times on the files over the web interface.
>> Can you report the output of something like a
>> 
>> # ls -Tla
> 
> Done and added to the web directory as file_dates:
> root@pelorus:/usr/src # ls -Tla *76*
> -rw-r--r--  1 root  wheel        0 Feb  2 13:52:42 2022 gtest-all-fe760c-d2733764.o.tmp
> -rw-r--r--  1 root  wheel  7339473 Feb  2 13:18:34 2022 gtest-all-fe760c.cpp
> -rw-r--r--  1 root  wheel  5246192 Feb  2 13:48:41 2022 gtest-all-fe760c.o
> -rw-r--r--  1 root  wheel     4527 Feb  2 13:18:34 2022 gtest-all-fe760c.sh
> -rw-r--r--  1 root  wheel     1448 Feb  2 13:35:26 2022 lldb-gtest-all-fe760c.sh

Thanks. That is the order for having a successful
gtest-all-fe760c.o generation when the lldb ran
the compile to completion with a zero status result
and later having the failing run. The gtest-all-fe760c.o
content is probably good.

>> We will see if I notice anything intersting looking at
>> source code related to the frames of the backtrace for
>> the lldb based failure reporting.

One of the odd things is that the bt command should
have reported a lot more frames than just #0..#5.
It should have gone all the way back to main and
__start and rtld_start . Another oddity that I've
no clue about at this point.

>> The variable results for the (lldb) .sh/.cpp runs for the
>> same file pair suggests possibilities like race conditions,
>> use of uninitialized memory, use of deallocated-and-reused
>> memory (now in-use for something else), flaky hardware.
>> 
>> (That failure only sometimes happened with the .sh/cpp
>> pair means that no processing of include files was involved:
>> the .cpp of the pair is self contained.)
>> 
>> I'll note that the buildworld.log 's :
>> 
>> 1.      /usr/obj/usr/src/arm64.aarch64/tmp/usr/include/private/gtest/internal/gtest-type-util.h:899:21: current parser token '{'
>> 2.      /usr/obj/usr/src/arm64.aarch64/tmp/usr/include/private/gtest/internal/gtest-type-util.h:58:1: parsing namespace 'testing'
>> 
>> is the exact same places in the original source code
>> as was reported in other such logs for failures while
>> processing gtest-all.cc .
>> 
>>> Not sure what to try next. It is possible to build kernel-toolchain and
>>> new kernels,
>> 
>> kernel-toolchain builds a subset of the toolchain that
>> buildworld builds. I'm unsure if the buildworld
>> completed building what kernel-toolchain builds or not.
>> 
>>> if that might be useful.
>> 
>> For now, I need to explore source code.
>> 
> 
> Ok, I'll refrain from idle tampering. 

Without being able to replicate the problem and explore
the context, I may well not get anywhere useful.

And nothing about this is suggesting any sort of work
around beyond building on a context that is not having
the issue and then installing from there to the media
that would be used on the RPi3* .

>>> At present the machine reports
>>> bob@pelorus:/usr/src % uname -apKU
>>> FreeBSD pelorus.zefox.org 13.0-STABLE FreeBSD 13.0-STABLE #0 stable/13-n249120-dee0854a009: Sat Jan 22 23:32:23 PST 2022     bob@pelorus.zefox.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC  arm64 aarch64 1300525 1300523
>> 
>> Thanks for the reference to stable/13 's dee0854a009 .
>> 
>> (This was still the "boot -s" single user context for
>> the testing. Note is for anyone reading this.)
>> 
>> FYI: the variable result makes the corrupted-block
>> hypothesis less likely. You have seen the failure via
>> the original files and via the .cpp of the .sh/.cpp
>> pair. You appear to have had a successful build
>> with the .cpp pair --and an unsuccessful one. Also
>> no stage under lldb reported illegal instructions or
>> the like.
>> 


===
Mark Millard
marklmi at yahoo.com