files: 0.987
graphic: 0.979
vnc: 0.947
boot: 0.942
device: 0.925
ppc: 0.921
architecture: 0.872
performance: 0.867
permissions: 0.846
peripherals: 0.832
user-level: 0.789
socket: 0.758
register: 0.735
kernel: 0.690
debug: 0.679
semantic: 0.649
PID: 0.646
network: 0.624
arm: 0.605
VMM: 0.603
risc-v: 0.568
virtual: 0.410
mistranslation: 0.334
hypervisor: 0.302
assembly: 0.277
TCG: 0.218
x86: 0.148
i386: 0.070
KVM: 0.057

qemu-system-ppc in Homebrew on macOS has mouse warps and ghost clicks
Description of problem:
The QEMU version in Homebrew (Intel macOS host, PowerPC Mac OS 9 guest) has random warping of the mouse cursor as well as ghost clicks which begin as soon as the operating system finishes loading. Video demonstration: https://youtu.be/DjXO0hwHArk

Notably, the exact same version of the QEMU source code with the same build arguments built *outside* of the Homebrew environment does not have this issue. I copied the following arguments from the QEMU Homebrew formula, and tried building QEMU on the command line:

    ../configure --prefix=/Users/josh/Desktop/qemu-homebrew-build --cc=clang --host-cc=clang --disable-bsd-user --disable-guest-agent --enable-capstone --enable-curses --enable-libssh --enable-slirp --enable-vde --enable-virtfs --enable-zstd --extra-cflags=-DNCURSES_WIDECHAR=1 --disable-sdl --smbd=/usr/local/sbin/samba-dot-org-smbd --disable-gtk --enable-cocoa --target-list=ppc-softmmu

This creates a `qemu-system-ppc` binary which is 15MB in size and works perfectly. By contrast, the exact same build commands within the Homebrew build process create a binary which is 10MB in size (!!!) and has this mouse warping and ghost clicks issue. This occurs whether QEMU was installed with `brew install qemu` or `brew install --build-from-source qemu`. Providing the `--HEAD` argument also makes no difference. The list of linked libraries (via `otool -L qemu-system-ppc`) is the same between the two versions.

The only way I can reproduce this issue outside of Homebrew is to dump the Homebrew environmental variables (with `env`) to a file and then set up those same environmental variables with the `source` command, after which the resulting `qemu-system-ppc` binary is now 10MB in size like the Homebrew version, and has the mouse issue like the Homebrew version. I'll attach the file with the Homebrew environmental variables. It seems that the issue must lie somewhere in there, but I'm really pushing the limits of my abilities, so I could definitely use some ideas and/or insights.
Steps to reproduce:
1. Install QEMU via `brew install qemu`
2. Start QEMU with an image of Mac OS 9
3. After the boot process completes, the issue manifests
Additional information:
[Homebrew_ENV_Variables.txt](/uploads/2393aed8f29fa9c32bcaca44281bd2a5/Homebrew_ENV_Variables.txt)