The autosetup version in this directory has been modified in order
to meet AdLib's needs. All changes can be found in the adlib.patch
file. They do the following:

* Always rely on the built-in JimTcl implementation and never on
  system tclsh to ensure that the build is reproducible and does
  not rely on tclsh-specific details that may not be available
  everywhere.
* Do not use ccache. We do not need it, as build times are fast
  enough, and during deployment we typically build only once,
  anyway.
* Prioritize gcc > clang > system cc, g++ > clang++ > system c++.
  We do not want to accidentally end up with a less powerful
  C/C++ compiler.
* Do not prepopulate CFLAGS with "-g -O2". For AdLib, optimization
  and debug flags go in OPT, not in CFLAGS.
* Add a missing message to cc-check-tools.