[pypy-issue] Issue #2473: Pypy2-5.7-alpha crash random for “cannot find gc roots!” (pypy/pypy)

[longriver]

New issue 2473: Pypy2-5.7-alpha crash random for “cannot find gc roots!”
https://bitbucket.org/pypy/pypy/issues/2473/pypy2-57-alpha-crash-random-for-cannot

longriver:

I build the version https://bitbucket.org/pypy/pypy/commits/b1c862cb933e (fix the FrontendTagOverflow crash), but the "cannot find gc roots!" crash occur a little more.

running environment: linux kernel 3.10.94, gcc 4.8.5, libffi.so.6.0.1, Intel Xeon E312xx (Sandy Bridge) 64 bits, other module: gevent-1.2.1 (with GEVENT_RESOLVER=ares)

the core dump info is:


```
#!python

Core was generated by `python -m main --name=mvp_count --appid=3'.
Program terminated with signal 6, Aborted.
#0  0x00007f12681e9625 in raise () from /lib64/libc.so.6
Missing separate debuginfos, use: debuginfo-install bzip2-libs-1.0.5-7.el6_0.x86_64 expat-2.0.1-9.1.el6.x86_64 glibc-2.12-1.149.tl1.6.x86_64 keyutils-libs-1.4-3.el6.x86_64 krb5-libs-1.9-22.el6_2.1.x86_64 libcom_err-1.41.12-11.el6.x86_64 libffi-3.0.5-3.2.el6.x86_64 libselinux-2.0.94-5.2.el6.x86_64 libuuid-2.17.2-12.5.tl1.x86_64 ncurses-libs-5.7-3.20090208.el6.x86_64 nss-softokn-freebl-3.12.9-11.el6.x86_64 openssl-1.0.1e-42.tl1.6.x86_64 zlib-1.2.3-27.el6.x86_64
(gdb) bt
#0  0x00007f12681e9625 in raise () from /lib64/libc.so.6
#1  0x00007f12681eae05 in abort () from /lib64/libc.so.6
#2  0x00007f126ac803e4 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#3  0x00007f126aceb683 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#4  0x00007f126ac760f8 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#5  0x00007f126ac767c1 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#6  0x00007f126ac774aa in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#7  0x00007f126ac77f41 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#8  0x00007f126ac78ada in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#9  0x00007f126ac7a898 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#10 0x00007f125e5c4c3f in ?? ()
#11 0x00007f126cd787b0 in ?? ()
#12 0x00007f125d92c05b in ?? ()
#13 0x00000000039ffc48 in ?? ()
#14 0x00007f1264d9d9a8 in ?? ()
#15 0x00007f126cd0c020 in ?? ()
#16 0x00007f126bae13c0 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#17 0x000000000000002d in ?? ()
#18 0x00007f1264da11e8 in ?? ()
#19 0x0000000003225bc0 in ?? ()
#20 0x00007f126aa349e2 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#21 0x00007f125e29c7b0 in ?? ()
#22 0x00007f126af7dc80 in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#23 0x00007fff88689fc8 in ?? ()
#24 0x00007fff88689e70 in ?? ()
#25 0x0000000000000003 in ?? ()
#26 0x00007f126cd787b1 in ?? ()
#27 0x00007f125d92eee6 in ?? ()
#28 0x0000000003225bc0 in ?? ()
#29 0x00007f126a9ab5fb in ?? () from /data/pypy2-5.7.0-alpha0-tlinux1.2/bin/libpypy-c.so
#30 0x00007f1268546e80 in ?? () from /lib64/libc.so.6
#31 0x0000000003d38850 in ?? ()
#32 0x00007f126cd0c020 in ?? ()
#33 0x0000000002657558 in ?? ()
#34 0x00007f125e29aa10 in ?? ()
#35 0x0000000000000000 in ?? ()
(gdb)
```