foo.cc: In function 'void init()':
foo.cc:15:46: warning: array subscript has type 'char' [-Wchar-subscripts]
   15 |     for (int i = 0; i < 64; i++) table[base[i]] = i;
      |                                        ~~~~~~^
foo.cc: In function 'void decode(char*)':
foo.cc:25:31: warning: array subscript has type 'char' [-Wchar-subscripts]
   25 |         (*ret++) = table[str[i]] << 2 | table[str[i + 1]] >> 4;
      |                          ~~~~~^
foo.cc:25:56: warning: array subscript has type 'char' [-Wchar-subscripts]
   25 |         (*ret++) = table[str[i]] << 2 | table[str[i + 1]] >> 4;
      |                                               ~~~~~~~~~^
foo.cc:27:40: warning: array subscript has type 'char' [-Wchar-subscripts]
   27 |             (*ret++) = (table[str[i + 1]] & 0x0f) << 4 | table[str[i + 2]] >> 2;
      |                               ~~~~~~~~~^
foo.cc:27:73: warning: array subscript has type 'char' [-Wchar-subscripts]
   27 |             (*ret++) = (table[str[i + 1]] & 0x0f) << 4 | table[str[i + 2]] >> 2;
      |                                                                ~~~~~~~~~^
foo.cc:29:39: warning: array subscript has type 'char' [-Wchar-subscripts]
   29 |             (*ret++) = table[str[i + 2]] << 6 | table[str[i + 3]];
      |                              ~~~~~~~~~^
foo.cc:29:64: warning: array subscript has type 'char' [-Wchar-subscripts]
   29 |             (*ret++) = table[str[i + 2]] << 6 | table[str[i + 3]];
      |                                                       ~~~~~~~~~^

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