anchor.diff:      __raw = true;
   
       gcc-unwrapped = null;
  -    glibc = null;
  +    glibc = assert false; null;
  +    musl = assert false; null;
       binutils = null;
       coreutils = null;
       gnugrep = null;
  
positive.code:       binutils = prevStage.binutils.override {
          # Rewrap the binutils with the new glibc, so both the next
          # stage's wrappers use it.
          libc = self.glibc;
        };
      };
    })
  
negative.code:           cc = prevStage.gcc-unwrapped;
            bintools = prevStage.binutils;
            isGNU = true;
            libc = getLibc prevStage;
            inherit (prevStage) coreutils gnugrep;
            name = name;
            stdenvNoCC = prevStage.ccWrapperStdenv;
  