Use the release tarball provided by the clisp maintainer.
Tested build by nix-build -A clisp -A clisp_2_44_1 -A gtk-server;
only clisp run-tested.
Of particular note is that the .so files no longer have executable
stacks. This also avoids executable stack in clisp lisp.run
Before:
$ readelf -lW $(nix-build -A clisp)/lib/clisp-2.49/base/lisp.run|grep GNU_STACK
GNU_STACK [...] RWE 0x10
After:
$ readelf -lW $(nix-build -A clisp)/lib/clisp-2.49/base/lisp.run|grep GNU_STACK
GNU_STACK [...] RW 0x10
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