Audio lossyness between different CPU architectures

[T-3B]

Recently I discovered a strange behavior with SAC.

Steps to reproduce:

• Choose a .wav file to encode, the longer the more likely the problem will occur.
• Encode a file on a specific CPU architecture (let's say x86-64). Any settings are fine (so for simplicity I chose the fastest - e.g. no argument given to sac).
• Decode the encoded file on a *different CPU architecture (let's say aarch64/ARM).
• Check the audio checksums with ffmpeg -v error -i <file.wav> -f streamhash -
• You will see that the decoded .wav does not match the input one (while if you used the same CPU architecture for both encoding and decoding they would match). You can also listen to the decoded file, warning: loud electronic noise.

Tested with aarch64 and x86-64, both with clang 16.0.6 and clang++ -O3 -flto -march=native -s

At least SAC encoding is architecture-dependent (different architectures will give different encoded SAC files - even the size).

On Mega, you can find the original WAV file, as well as the aarch64 and x86-64 SAC encoded files.

[sergeevabc]

@T-3B, which SAC version do you use? Github has 0.5.1, EncodeSu has 0.6.3.

[T-3B]

@sergeevabc I compiled myself the master branch (with a very few extras in my fork). I also made some releases there with LTO and PGO and different CPU architectures (aarch64 and x86_64). So it is 0.6.3.

[T-3B]

Oh, I forgot about that one: #2

Apparently not only because of different CPU architecture, but different OS too.

[sergeevabc]

Hmm, where can I get the binary of version 0.6.7 with “a small fix”?