This was reported by kery on Discord.

Emerge fails at compile phase with the following error message:

/var/tmp/portage/app-crypt/veracrypt-1.24_p7/work/VeraCrypt-VeraCrypt_1.24-Update7/src/Crypto/Aes_hw_cpu.h:27:32: error: reference to ‘byte’ is ambiguous
   27 | void aes_hw_cpu_decrypt (const byte *ks, byte *data);
      |                                ^~~~
In file included from /var/tmp/portage/app-crypt/veracrypt-1.24_p7/work/VeraCrypt-VeraCrypt_1.24-Update7/src/Platform/PlatformBase.h:16,
                 from /var/tmp/portage/app-crypt/veracrypt-1.24_p7/work/VeraCrypt-VeraCrypt_1.24-Update7/src/Platform/Platform.h:16,
                 from EncryptionAlgorithm.h:16,
                 from EncryptionAlgorithm.cpp:13:
/usr/lib/gcc/x86_64-pc-linux-gnu/11.3.0/include/g++-v11.3.0/cstddef:69:14: note: candidates are: ‘enum class std::byte’

See build.log for a complete build log.

This looks like a matter of missing header or maybe a using statement to make clear which namespace the type should be pulled from, but this is actually a C code section guarded by "extern_C".

I don't know how to solve this in the code because std::byte shouldn't even be accessible <cstddef> (which is where std::byte) is supposed to be defined wasn't even #included in this file. Upstream developers didn't bother to patch the code either (the Github master head still has the same code).

The fact is that std::byte only exists in C+17 upwards, so this is a problem that happens in systems with GCC>=11, which has -std=c17 by default. The solution they came up with was to patch their Makefile, so that if GCC>=11 is detected, it will add -std=gnu+14 to CXXFLAGS. That patch should be incorporated from v.1.25.4 on.

Therefore, there are 3 possible solutions to this issue, any of which will be enough to resolve this issue:

1. - Simple add the following line to src_prepare():

   append-cxxflags -std=gnu\+\+14

1. - Apply this patch to change the Makefile.
2. - Upgrade the package to a version >= 1.25.4 (and possibly autogen the package).