'brew update' reports many exceptions

[cang-mang]

I do brew update today, and it reports:

...
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `each'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `flat_map'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `global_deps_for'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:70:in `block in global_deps_for'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `each'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `flat_map'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:69:in `global_deps_for'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/extend/os/linux/dependency_collector.rb:50:in `init_global_dep_tree_if_needed!'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dependency_collector.rb:33:in `initialize'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/software_spec.rb:42:in `new'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/software_spec.rb:42:in `initialize'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2697:in `new'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2697:in `block in inherited'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2695:in `instance_eval'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2695:in `inherited'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/gcc.rb:1:in `block in load_formula'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:90:in `module_eval'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:90:in `block in load_formula'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:102:in `load_formula'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:122:in `load_formula_from_path'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:322:in `load_file'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:479:in `load_file'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:312:in `klass'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:307:in `get_formula'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:469:in `get_formula'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:561:in `factory'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:609:in `from_keg'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formulary.rb:582:in `from_rack'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:1855:in `block in installed'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:1854:in `each'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:1854:in `flat_map'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:1854:in `installed'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/upgrade.rb:135:in `upgrade_outdated_formulae'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/upgrade.rb:116:in `upgrade'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/brew.rb:95:in `<main>'

The brew upgrade also reports these.

[p-linnane]

What is the output of brew doctor and brew config? Have you tried brew update-reset && brew update?

[cang-mang]

Today I run brew update-reset, and then brew update, and then brew upgrade. It works. Thank you very much!