Error when importing after compiling with GCC 10

[Gelbpunkt]

• asyncpg version: asyncpg-0.21.0.dev0+7f5c2a2 (same for 0.20.1)
• PostgreSQL version: does not matter
• Do you use a PostgreSQL SaaS? If so, which? Can you reproduce
  the issue with a local PostgreSQL install?: does not matter
• Python version: 3.8.2 and 3.9.0a5+
• Platform: Fedora 32 x64/aarch64 and Alpine Linux 3.12 alpha x64/aarch64
• Do you use pgbouncer?: does not matter
• Did you install asyncpg with pip?: no
• If you built asyncpg locally, which version of Cython did you use?: 0.29.16 and 3.0a2
• Can the issue be reproduced under both asyncio and
  uvloop?: does not matter

I have tested this on the following scenarios:
Fedora 32 x86_64, Python 3.8.2, GCC 10.0.1 20200328 (Red Hat 10.0.1-0.11) from official repos
Fedora 33 (rawhide) aarch64, Python 3.8.2, GCC 10.0.1 20200420 (Red Hat 10.0.1-0.12) from official repos
Alpine Linux 3.12 alpha x86_64, Python 3.9a5, GCC 10.0.1 20200427 from source (builds at https://ftp.travitia.xyz/alpine/x86_64/)
Alpine Linux 3.12 alpha aarch64, Python 3.9a5, GCC 10.0.1 20200426 from source (builds at https://ftp.travitia.xyz/alpine/aarch64/)
All have been tested twice with Cython 0.29.16 and Cython 3.0a2.

Whenever I compile asyncpg with GCC 9.3 on any of above scenarios, it compiles fine and runs fine.
Whenever I use GCC 10 in any of above scenarios, it does build fine, but importing it gives me:

>>> import asyncpg
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/jens/.local/lib/python3.8/site-packages/asyncpg/__init__.py", line 8, in <module>
    from .connection import connect, Connection  # NOQA
  File "/home/jens/.local/lib/python3.8/site-packages/asyncpg/connection.py", line 19, in <module>
    from . import connect_utils
  File "/home/jens/.local/lib/python3.8/site-packages/asyncpg/connect_utils.py", line 28, in <module>
    from . import protocol
  File "/home/jens/.local/lib/python3.8/site-packages/asyncpg/protocol/__init__.py", line 8, in <module>
    from .protocol import Protocol, Record, NO_TIMEOUT  # NOQA
  File "asyncpg/protocol/protocol.pyx", line 1, in init asyncpg.protocol.protocol
ImportError: /home/jens/.local/lib/python3.8/site-packages/asyncpg/pgproto/pgproto.cpython-38-x86_64-linux-gnu.so: undefined symbol: uuid_to_hex

This is weird, as readelf shows:

$ readelf -a /home/jens/.local/lib/python3.8/site-packages/asyncpg/pgproto/pgproto.cpython-38-x86_64-linux-gnu.so | grep uuid_to_hex
000000055d90  004f00000007 R_X86_64_JUMP_SLO 0000000000000000 uuid_to_hex + 0
    79: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND uuid_to_hex
  1176: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND uuid_to_hex

I don't know C much, but I have seen that uuid_to_hex is defined in the code for pgproto, so I have no clue how this happens.

FYI: On all scenarios, I am able to compile and use uvloop and cpython 3.9 without any errors.

EDIT: Same issue with Alpine Linux 3.12 alpha, Python 3.9a6, Cython 3.0a3 and GCC 10 20200430

[Gelbpunkt]

The error persists with GCC 10.1, the first stable GCC 10 release (https://gcc.gnu.org/).
Example with python 3.9a6+ in alpine 3.12 alpha:

/ # readelf -a /usr/local/lib/python3.9/site-packages/asyncpg/pgproto/pgproto.cpython-39-x86_64-linux-gnu.so | grep uuid_to_hex
000000046b48  002a00000007 R_X86_64_JUMP_SLO 0000000000000000 uuid_to_hex + 0
    42: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND uuid_to_hex
  1258: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND uuid_to_hex

[ioistired]

Seems to be related to #534

[kamikaze]

getting same issue with gcc 10.1 on ARM64

$ python
Python 3.8.3 (default, May 29 2020, 07:06:49) 
[GCC 10.1.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from asyncpg import PG
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/kamikaze/projects/proj/.venv38/lib/python3.8/site-packages/asyncpg/__init__.py", line 8, in <module>
    from .connection import connect, Connection  # NOQA
  File "/home/kamikaze/projects/proj/.venv38/lib/python3.8/site-packages/asyncpg/connection.py", line 19, in <module>
    from . import connect_utils
  File "/home/kamikaze/projects/proj/.venv38/lib/python3.8/site-packages/asyncpg/connect_utils.py", line 27, in <module>
    from . import protocol
  File "/home/kamikaze/projects/proj/.venv38/lib/python3.8/site-packages/asyncpg/protocol/__init__.py", line 8, in <module>
    from .protocol import Protocol, Record, NO_TIMEOUT  # NOQA
  File "asyncpg/protocol/protocol.pyx", line 1, in init asyncpg.protocol.protocol
ImportError: /home/kamikaze/projects/proj/.venv38/lib/python3.8/site-packages/asyncpg/pgproto/pgproto.cpython-38-aarch64-linux-gnu.so: undefined symbol: uuid_to_hex