GCC stopped permitting referencing a packed field.

[puellanivis]

ppc_fpu.cc: In function ‘void ppc_opc_frsqrtex(PPC_CPU_State&)’:
ppc_fpu.cc:1870:63: error: cannot bind packed field ‘aCPU.PPC_CPU_State::fpr[frD]’ to ‘uint64&’ {aka ‘long unsigned int&’}
 1870 |  aCPU.fpscr |= ppc_fpu_pack_double(aCPU.fpscr, D, aCPU.fpr[frD]);
      |                                                   ~~~~~~~~~~~~^

Apparently, the C++ standards changed at some point, and referencing into a packed struct, means that you cannot guarantee alignment, which could cause issues on some architectures that do not permit unaligned accesses, so GCC decided that this dictates that the code should be prevented from compiling.

GCC version info:

pearpc$ g++ --version
g++ (SUSE Linux) 9.1.1 20190611 [gcc-9-branch revision 272147]

[Shoegzer]

Confirmed here too, on linux mint 20, kernel 5.4 and gcc 9.3.0

[Hodapp87]

Confirmed on NixOS as well. Locking to GCC 8 works.

[nesper8]

Confirmed and reproducable on EndeavourOS as well (Arch based) with GCC version 10.1.0

Ill try to compile out on a ubuntu18 docker image which still have both 7.1.0 and 8.0.0 GCC

Update:
docker build seems successful but yet to test it as i dont have a valid MacOSX disk file rn
I'll make a release in my fork if that doesn't breach GPLv2

Sry for bad english