brew install ffmpeg@6 fails on linux

[ipatch]

Output of brew config

HOMEBREW_VERSION: 4.4.6-45-g3b1d59d
ORIGIN: https://github.com/Homebrew/brew
HEAD: 3b1d59d8c4fbf8c0ba0c9752007ff27bec3bc8b3
Last commit: 25 hours ago
Core tap origin: https://github.com/ipatch/homebrew-core.git
Core tap HEAD: 68f9567f4062aa4295132e738cb39259557303b2
Core tap last commit: 19 minutes ago
Core tap branch: ipatch.archlinux.ffmpeg@6
HOMEBREW_PREFIX: /home/capin/homebrew
HOMEBREW_REPOSITORY: /home/capin/homebrew
HOMEBREW_CELLAR: /home/capin/homebrew/Cellar
HOMEBREW_CACHE: /home/capin/homebrew/cache
HOMEBREW_CASK_OPTS: []
HOMEBREW_DEVELOPER: set
HOMEBREW_DISPLAY: :0
HOMEBREW_EDITOR: nvim
HOMEBREW_FORCE_VENDOR_RUBY: set
HOMEBREW_GITHUB_API_TOKEN: set
HOMEBREW_MAKE_JOBS: 4
HOMEBREW_NO_ANALYTICS: set
HOMEBREW_NO_AUTOREMOVE: set
HOMEBREW_NO_AUTO_UPDATE: set
HOMEBREW_NO_GITHUB_API: set
HOMEBREW_NO_INSTALL_CLEANUP: set
HOMEBREW_NO_INSTALL_FROM_API: set
HOMEBREW_SORBET_RUNTIME: set
HOMEBREW_TEMP: /opt/tmp/homebrew
Homebrew Ruby: 3.3.6 => /home/capin/homebrew/Library/Homebrew/vendor/portable-ruby/3.3.6/bin/ruby
CPU: octa-core 64-bit haswell
Clang: 19.1.3
Git: 2.47.0 => /bin/git
Curl: 8.11.0 => /bin/curl
Kernel: Linux 6.6.62-1-lts x86_64 GNU/Linux
OS: Arch Linux
Host glibc: 2.40
/usr/bin/gcc: 14.2.1
/usr/bin/ruby: 3.3.5
glibc: N/A
gcc@11: N/A
gcc: 14.2.0_1
xorg: N/A

Output of brew doctor

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Warning: Suspicious https://github.com/Homebrew/homebrew-core git origin remote found.
The current git origin is:
  https://github.com/ipatch/homebrew-core.git

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You can solve this by setting the origin remote:
  git -C "/home/capin/homebrew/Library/Taps/homebrew/homebrew-core" remote set-url origin https://github.com/Homebrew/homebrew-core

Warning: Some installed kegs have no formulae!
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  python-ply

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Warning: You have external commands with conflicting names.
Found command `brew-install-asahi` in the following places:
  /home/capin/homebrew/Library/Taps/ipatch/homebrew-us-05/cmd/brew-install-asahi.rb
  /home/capin/homebrew/Library/Taps/ipatch/us05/cmd/brew-install-asahi.rb

Warning: You have unlinked kegs in your Cellar.
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Error: /home/capin/homebrew/Cellar/ffmpeg/7.1_3 is not a directory

Description of issue

brew install ffmpeg@6 fails with my current homebrew setup in a custom prefix on arch linux ie. ~/homebrew

i am only able to build using the provided patch file.

https://git.videolan.org/?p=ffmpeg.git;a=patch;h=1f801dfdb5066aadf0ade9cb5e94d620f33eacdc

i created a branch on my fork of homebrew-core that applies the patch and successfully builds ffmpeg@6.

how are y'all able to build ffmpeg@6 without this patch? noticing there's a bottle in the formula.

https://github.com/Homebrew/homebrew-core/blob/master/Formula/f/ffmpeg%406.rb#L22

i copy pasted the error message from the build process in my formula file for ffmpeg@6

https://github.com/ipatch/homebrew-core/blob/68f9567f4062aa4295132e738cb39259557303b2/Formula/f/ffmpeg%406.rb#L108