Two ARM64-specific compiler optimization bugs, in GCC 15/16 and Rust, hit curl

The curl project has been affected by two ARM64-specific compiler optimization bugs in GCC 15 and 16, as well as a similar issue in the Rust compiler. These bugs can cause incorrect results or crashes when curl is compiled with the -O3 optimization level. The bugs have been fixed in the latest versions of GCC and Rust. The curl project has also released an updated version to address the issue. The bugs were discovered by a security researcher who was investigating a crash in curl.