Thankyou Felix.
--
Namrata Jain
On 26.05.2020 22:02, Felix Rath wrote:
Hey,
As suggested, I ran "make check" from klee-build-directory and found
that 47 unexpected tests were failing.
That definitely sounds like something might have been broken there.
What this error is about? I also found this as an open issue on klee
github page.
I sadly cannot help with this, as I don't use KLEE's build scripts,
and am not really familiar with how they work at all. So I don't know
what the correct options, usage, etc. for building KLEE with libcxx
support are.
As you mentioned that libcxx support was not required for the example
I
stated, I built klee (version 2.1) without enabling libcxx and was
able
to see the output "12" with no errors.
Nice :) Then I would assume that LLVM 9 or 10 should definitely help
with running with `--libcxx`.
Are these due to not linking libcxx?
KLEE: WARNING: undefined reference to function: _ZSt9terminatev
KLEE: WARNING: undefined reference to function: __cxa_begin_catch
KLEE: WARNING: undefined reference to function: __gxx_personality_v0
I think these are from not linking libcxxabi, which can be part of
libcxx depending on how you build it.
KLEE: WARNING: undefined reference to function: __syscall_rt_sigaction
KLEE: WARNING: undefined reference to function: fcntl
KLEE: WARNING: undefined reference to function: fstat
KLEE: WARNING: undefined reference to function: ioctl
KLEE: WARNING: undefined reference to function: llvm.dbg.label
KLEE: WARNING: undefined reference to function: open
KLEE: WARNING: undefined reference to function: write
KLEE: WARNING: undefined reference to function: kill (UNSAFE)!
Some of these actually are provided by --posix-runtime (like `open`,
`ioctl` and maybe more), so that might help here. Others might not be
modeled for KLEE (yet), but they don't seem to be from libcxx, as
libcxx usually contains C++-mangled names (but they might appear in
the program because you #include'd and ).
I also want to know about klee version-2.1-pre, is it the same as
version 2.0? This is because I have made some changes in my klee
source
(2.1-pre) for a project and now I will be using version-2.1.
Can't really help with this, not really familiar with KLEE's release
process.
Best,
Felix
From: Namrata Jain
Sent: Tuesday, May 26, 2020 2:32 PM
To: Felix Rath
Cc: klee-dev@imperial.ac.uk
Subject: Re: [klee-dev] Error while using C++ STL, libcxx
Hello Felix,
Thankyou for the reply.
As suggested, I ran "make check" from klee-build-directory and found
that 47 unexpected tests were failing.
So, I installed llvm-10, but while installing libcxx from
klee-source-directory using the command:
LLVM_VERSION=10 SANITIZER_BUILD= BASE=
./scripts/build/build.sh libcxx
it generated output:
Detected OS: linux
OS=linux
Detected distribution: ubuntu
DISTRIBUTION=ubuntu
Detected version: 18.04
DISTRIBUTION_VER=18.04
Component sanitizer not found.
Component sanitizer not found.
ENABLE_OPTIMIZED Required but unset
What this error is about? I also found this as an open issue on klee
github page.
As you mentioned that libcxx support was not required for the example I
stated, I built klee (version 2.1) without enabling libcxx and was able
to see the output "12" with no errors.
(using the command: klee --libc=uclibc /experiment.bc)
Warnings that were generated:
KLEE: WARNING: undefined reference to function: _ZSt9terminatev
KLEE: WARNING: undefined reference to function: __cxa_begin_catch
KLEE: WARNING: undefined reference to function: __gxx_personality_v0
KLEE: WARNING: undefined reference to function: __syscall_rt_sigaction
KLEE: WARNING: undefined reference to function: fcntl
KLEE: WARNING: undefined reference to function: fstat
KLEE: WARNING: undefined reference to function: ioctl
KLEE: WARNING: undefined reference to function: llvm.dbg.label
KLEE: WARNING: undefined reference to function: open
KLEE: WARNING: undefined reference to function: write
KLEE: WARNING: undefined reference to function: kill (UNSAFE)!
KLEE: WARNING ONCE: calling external: ioctl(0, 21505, 94590150907232)
at
libc/termios/tcgetattr.c:43 12
KLEE: WARNING ONCE: calling __user_main with extra arguments.
Are these due to not linking libcxx?
I also want to know about klee version-2.1-pre, is it the same as
version 2.0? This is because I have made some changes in my klee source
(2.1-pre) for a project and now I will be using version-2.1.
Thankyou.
--
Namrata Jain
On 25.05.2020 17:21, Felix Rath wrote:
Hello Namrata,
I worked a lot on the current C++ support in KLEE (the recent C++
support PRs to KLEE were by me), so I hope I can help. I think the
main problem is that llvm 6.0 is quite old, and your example should
pretty much work as-is if you switch to a recent llvm version (the
most recent being 10, which should work). I tried your example locally
with llvm (and libc++) 10 and it produced the expected output ("12").
You can also run
