log

Error in src/compiler/crystal.cr:6: instantiating 'Crystal::Command:Class#run()'

Crystal::Command.run
                 ^~~

in src/compiler/crystal/command.cr:47: instantiating 'run(Array(String))'

  def self.run(options = ARGV)
  ^

in src/compiler/crystal/command.cr:48: instantiating 'Crystal::Command#run()'

    new(options).run
                 ^~~

in src/compiler/crystal/command.cr:70: instantiating 'build()'

        build
        ^~~~~

in src/compiler/crystal/command.cr:170: instantiating 'Crystal::Command::CompilerConfig#compile()'

    config.compile
           ^~~~~~~

in src/compiler/crystal/command.cr:244: instantiating 'compile(String)'

    def compile(output_filename = self.output_filename)
    ^

in src/compiler/crystal/command.cr:246: instantiating 'Crystal::Compiler#compile(Array(Crystal::Compiler::Source), String)'

      compiler.compile sources, output_filename
               ^~~~~~~

in src/compiler/crystal/compiler.cr:125: instantiating 'new_program(Array(Crystal::Compiler::Source))'

      program = new_program(source)
                ^~~~~~~~~~~

in src/compiler/crystal/compiler.cr:155: undefined method 'merge!' for Set(String) (did you mean 'merge'?)

      program.flags.merge! @flags
                    ^~~~~~

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