Initialization order... or something.

[winapiadmin]

I don't know how to describe this...

Step 1: build the library
Step 2:

#include <attacks.h>
int main(){
    return chess::attacks::bishop(chess::SQ_A1,0);
}

Step 3: build the program with the library
Step 4:

gdb ./a.out
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Reading symbols from ./a.out...
(gdb) r
Starting program: /mnt/c/Users/winapiadmin/Desktop/chess_engine/build2/chesslib/a.out

This GDB supports auto-downloading debuginfo from the following URLs:
  <https://debuginfod.ubuntu.com>
Enable debuginfod for this session? (y or [n]) y
Debuginfod has been enabled.
To make this setting permanent, add 'set debuginfod enabled on' to .gdbinit.
Downloading separate debug info for system-supplied DSO at 0x7ffff7fc3000
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
0x0000555555555b68 in chess::attacks::generate_magic_table<chess::_chess::_HyperbolaBishopAttacks, 5248, true> () at /mnt/c/Users/winapiadmin/Desktop/chess_engine/build2/chesslib/attacks.cpp:170
170                 attacks[offset + idx] = AttackFunc(static_cast<Square>(sq), occ);
(gdb) r
The program being debugged has been started already.
Start it from the beginning? (y or n) n
Program not restarted.
(gdb) bt
#0  0x0000555555555b68 in chess::attacks::generate_magic_table<chess::_chess::_HyperbolaBishopAttacks, 5248, true> () at /mnt/c/Users/winapiadmin/Desktop/chess_engine/build2/chesslib/attacks.cpp:170
#1  0x0000555555555f46 in __static_initialization_and_destruction_0 () at /mnt/c/Users/winapiadmin/Desktop/chess_engine/build2/chesslib/attacks.cpp:180
#2  0x0000555555556000 in _GLOBAL__sub_I__ZN5chess7attacks10RookMagicsE () at /mnt/c/Users/winapiadmin/Desktop/chess_engine/build2/chesslib/attacks.cpp:211
#3  0x00007ffff7c2a304 in call_init (env=<optimized out>, argv=0x7fffffffd708, argc=1) at ../csu/libc-start.c:145
#4  __libc_start_main_impl (main=0x5555555551a9 <main>, argc=1, argv=0x7fffffffd708, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffd6f8) at ../csu/libc-start.c:347
#5  0x00005555555550e5 in _start ()
(gdb) quit
A debugging session is active.

        Inferior 1 [process 1337] will be killed.

Quit anyway? (y or n) y

Workaround: Move rook and bishop attack generation to source file

... but why?