I have tried running it like this to no avail. clang++ -std=c++11 -O3 -ffast-math -mllvm -enable-constraint-elimination=0 \ main.cpp -o out/main Note, I had to chang @Signalsmith 's original makefile from g++ to clang++ to allow me to also test clang 19 as installed by brew. This image should show the difference(s) between Apple Clang 15, 16 and a baseline Clang.

To confirm, I can reproduce this on another machine with a different processor and have tested using different compilers. Apple clang 15.0.0 reports no errors clang version 19.1.5 (via llvm via brew install llvm) reports tiny errors as you might expect with relaxed float compliance. Apple clang 16.0.0 is wildly different (imaginary portion have their sign flipped). Would be super nice if Apple could comment on this and what the timeline might be for a fix. Thanks!

CFURLRequestSetHTTPCookieStorageAcceptPolicyblock_invoke: no longer implemented and should not be called is an erronious error message. I get it no matter what I do with altool on big sur, whether my operation succeeds or not. It did however mess up my build scripts as I was relying on something like this to pipe the output to a file to then scan for the outcome. xcrun altool --notarize-app --primary-bundle-id com.ursadsp.pkg.Lagrange --username "email@example.com" --password "@keychain:Plugin Notarization Password" -f ./installer/build/Lagrange.pkg --output-format xml &> ./installer/build/notarize-app.xml The solution was to drop the & before the > as that extra message is sent to stderr not stdout.