CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required):
  Compatibility with CMake < 3.10 will be removed from a future version of
  CMake.

  Update the VERSION argument <min> value.  Or, use the <min>...<max> syntax
  to tell CMake that the project requires at least <min> but has been updated
  to work with policies introduced by <max> or earlier.

CMake Warning (dev) at /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:430 (message):
  The package name passed to find_package_handle_standard_args() (PkgConfig)
  does not match the name of the calling package (PCRE2).  This can lead to
  problems in calling code that expects find_package() result variables
  (e.g., `_FOUND`) to follow a certain pattern.
Call Stack (most recent call first):
  /usr/share/cmake/Modules/FindPkgConfig.cmake:108 (find_package_handle_standard_args)
  cmake/FindPCRE2.cmake:8 (include)
  CMakeLists.txt:50 (find_package)
This warning is for project developers.  Use -Wno-dev to suppress it.

/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_encode_decode':
/srv/shadowsocks-libev/tests/test_base64.c:19:9: warning: unused variable 'decoded_len' [-Wunused-variable]
   19 |     int decoded_len = base64_decode(decoded, encoded, sizeof(decoded));
      |         ^~~~~~~~~~~
/srv/shadowsocks-libev/tests/test_base64.c:15:11: warning: unused variable 'ret' [-Wunused-variable]
   15 |     char *ret = base64_encode(encoded, sizeof(encoded), input, 5);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_empty_input':
/srv/shadowsocks-libev/tests/test_base64.c:28:11: warning: unused variable 'ret' [-Wunused-variable]
   28 |     char *ret = base64_encode(encoded, sizeof(encoded), (const uint8_t *)"", 0);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_single_byte':
/srv/shadowsocks-libev/tests/test_base64.c:43:9: warning: unused variable 'decoded_len' [-Wunused-variable]
   43 |     int decoded_len = base64_decode(decoded, encoded, sizeof(decoded));
      |         ^~~~~~~~~~~
/srv/shadowsocks-libev/tests/test_base64.c:40:11: warning: unused variable 'ret' [-Wunused-variable]
   40 |     char *ret = base64_encode(encoded, sizeof(encoded), input, 1);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_two_bytes':
/srv/shadowsocks-libev/tests/test_base64.c:58:9: warning: unused variable 'decoded_len' [-Wunused-variable]
   58 |     int decoded_len = base64_decode(decoded, encoded, sizeof(decoded));
      |         ^~~~~~~~~~~
/srv/shadowsocks-libev/tests/test_base64.c:55:11: warning: unused variable 'ret' [-Wunused-variable]
   55 |     char *ret = base64_encode(encoded, sizeof(encoded), input, 2);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_three_bytes':
/srv/shadowsocks-libev/tests/test_base64.c:74:9: warning: unused variable 'decoded_len' [-Wunused-variable]
   74 |     int decoded_len = base64_decode(decoded, encoded, sizeof(decoded));
      |         ^~~~~~~~~~~
/srv/shadowsocks-libev/tests/test_base64.c:71:11: warning: unused variable 'ret' [-Wunused-variable]
   71 |     char *ret = base64_encode(encoded, sizeof(encoded), input, 3);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_roundtrip_binary':
/srv/shadowsocks-libev/tests/test_base64.c:92:9: warning: unused variable 'decoded_len' [-Wunused-variable]
   92 |     int decoded_len = base64_decode(decoded, encoded, sizeof(decoded));
      |         ^~~~~~~~~~~
/srv/shadowsocks-libev/tests/test_base64.c:89:11: warning: unused variable 'ret' [-Wunused-variable]
   89 |     char *ret = base64_encode(encoded, sizeof(encoded), input, 17);
      |           ^~~
/srv/shadowsocks-libev/tests/test_base64.c: In function 'test_invalid_chars':
/srv/shadowsocks-libev/tests/test_base64.c:101:9: warning: unused variable 'decoded_len' [-Wunused-variable]
  101 |     int decoded_len = base64_decode((uint8_t[4]){}, "!!!!", 4);
      |         ^~~~~~~~~~~