i can't install tk

[0xNinjaCyclone]

~# gem install tk
Building native extensions. This could take a while...
ERROR: Error installing tk:
ERROR: Failed to build gem native extension.

current directory: /var/lib/gems/2.7.0/gems/tk-0.2.0/ext/tk

/usr/bin/ruby2.7 -I /usr/local/lib/site_ruby/2.7.0 -r ./siteconf20201007-7660-1i5ky4m.rb extconf.rb
check functions.checking for ruby_native_thread_p() in ruby.h... yes
checking for rb_errinfo() in ruby.h... yes
checking for rb_safe_level() in ruby.h... yes
checking for rb_hash_lookup() in ruby.h... yes
checking for rb_proc_new() in ruby.h... yes
checking for rb_obj_untrust() in ruby.h... yes
checking for rb_obj_taint() in ruby.h... yes
checking for rb_set_safe_level_force() in ruby.h... yes
checking for rb_sourcefile() in ruby.h... yes
checking for rb_thread_alive_p() in ruby.h... no
checking for rb_thread_check_trap_pending() in ruby.h... yes
checking for ruby_enc_find_basename() in ruby.h... yes
check libraries.checking for t_open() in -lnsl... no
checking for socket() in -lsocket... no
checking for dlopen() in -ldl... yes
checking for log() in -lm... yes
Use ActiveTcl libraries (if available).
Search tclConfig.sh and tkConfig.sh.
WARNING: found "/usr/lib/tclConfig.sh", but cannot find valid Tcl library for the tclConfig.sh. So, ignore it.

WARNING: found "/usr/lib/tkConfig.sh", but cannot find valid Tk library for the tkConfig.sh. So, ignore it.

WARNING: found "/lib/tclConfig.sh", but cannot find valid Tcl library for the tclConfig.sh. So, ignore it.

WARNING: found "/lib/tkConfig.sh", but cannot find valid Tk library for the tkConfig.sh. So, ignore it.

Fail to find [tclConfig.sh, tkConfig.sh]
Use X11 libraries (or use TK_XINCLUDES/TK_XLIBSW information on tkConfig.sh).
checking for XOpenDisplay() in -lX11... yes
Search tcl.h
checking for tcl.h... no
Search tk.h
checking for tk.h... no
Search Tcl library.........*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.

Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/usr/bin/$(RUBY_BASE_NAME)2.7
--enable-shared
--with-tk-old-extconf
--without-tk-old-extconf
--with-tk-old-extconf
--without-tk-old-extconf
--with-ActiveTcl
--without-ActiveTcl
--with-tk-shlib-search-path
--without-tk-shlib-search-path
--with-tcltkversion
--without-tcltkversion
--with-tcl-build-dir
--without-tcl-build-dir
--with-tk-build-dir
--without-tk-build-dir
--with-tcl-config
--without-tcl-config
--with-tk-config
--without-tk-config
--with-tclConfig-dir
--without-tclConfig-dir
--with-tkConfig-dir
--without-tkConfig-dir
--with-tclConfig-file
--without-tclConfig-file
--with-tkConfig-file
--without-tkConfig-file
--with-tcllib
--without-tcllib
--with-tklib
--without-tklib
--with-tcl-dir
--without-tcl-dir
--with-tk-dir
--without-tk-dir
--with-tcl-include
--without-tcl-include
--with-tk-include
--without-tk-include
--with-tcl-lib
--without-tcl-lib
--with-tk-lib
--without-tk-lib
--with-tcltk-framework
--without-tcltk-framework
--with-tcl-framework-dir
--without-tcl-framework-dir
--with-tk-framework-dir
--without-tk-framework-dir
--with-tcl-framework-header
--without-tcl-framework-header
--with-tk-framework-header
--without-tk-framework-header
--with-X11
--without-X11
--with-X11-dir
--without-X11-dir
--with-X11-include
--without-X11-include
--with-X11-lib
--without-X11-lib
--enable-tcltk-stubs
--disable-tcltk-stubs
--enable-tcl-h-ver-check
--disable-tcl-h-ver-check
--enable-tk-h-ver-check
--disable-tk-h-ver-check
--enable-mac-tcltk-framework
--disable-mac-tcltk-framework
--enable-tcltk-framework
--disable-tcltk-framework
--enable-pthread
--disable-pthread
--enable-tcl-thread
--disable-tcl-thread
--enable-space-on-tk-libpath
--disable-space-on-tk-libpath
--with-nsl-dir
--without-nsl-dir
--with-nsl-include
--without-nsl-include=${nsl-dir}/include
--with-nsl-lib
--without-nsl-lib=${nsl-dir}/lib
--with-nsllib
--without-nsllib
--with-socket-dir
--without-socket-dir
--with-socket-include
--without-socket-include=${socket-dir}/include
--with-socket-lib
--without-socket-lib=${socket-dir}/lib
--with-socketlib
--without-socketlib
--with-dl-dir
--without-dl-dir
--with-dl-include
--without-dl-include=${dl-dir}/include
--with-dl-lib
--without-dl-lib=${dl-dir}/lib
--with-dllib
--without-dllib
--with-m-dir
--without-m-dir
--with-m-include
--without-m-include=${m-dir}/include
--with-m-lib
--without-m-lib=${m-dir}/lib
--with-mlib
--without-mlib
--with-tcl-build-dir
--without-tcl-build-dir
--with-tk-build-dir
--without-tk-build-dir
--with-tcltkversion
--without-tcltkversion
--with-ActiveTcl
--without-ActiveTcl
--enable-space-on-tk-libpath
--disable-space-on-tk-libpath
--enable-tcltk-stubs
--disable-tcltk-stubs
--with-tcltk-stubs
--without-tcltk-stubs
--with-tcl-dir
--without-tcl-dir
--with-tcl-include
--without-tcl-include=${tcl-dir}/include
--with-tcl-lib
--without-tcl-lib=${tcl-dir}/lib
--with-tk-dir
--without-tk-dir
--with-tk-include
--without-tk-include=${tk-dir}/include
--with-tk-lib
--without-tk-lib=${tk-dir}/lib
--with-tclConfig-file
--without-tclConfig-file
--with-tkConfig-file
--without-tkConfig-file
--with-tclConfig-dir
--without-tclConfig-dir
--with-tkConfig-dir
--without-tkConfig-dir
--with-tcl-framework-header
--without-tcl-framework-header
--with-tk-framework-header
--without-tk-framework-header
--with-tcl-framework-dir
--without-tcl-framework-dir
--with-tk-framework-dir
--without-tk-framework-dir
--with-tcltk-framework
--without-tcltk-framework
--enable-tcltk-framework
--disable-tcltk-framework
--with-tcltk-framework
--without-tcltk-framework
--enable-tcltk-framework
--disable-tcltk-framework
--enable-mac-tcltk-framework
--disable-mac-tcltk-framework
--with-tk-shlib-search-path
--without-tk-shlib-search-path
--with-tklib
--without-tklib
--with-tcllib
--without-tcllib
--with-X11
--without-X11
--with-X11-dir
--without-X11-dir
--with-X11-include
--without-X11-include=${X11-dir}/include
--with-X11-lib
--without-X11-lib=${X11-dir}/lib
--with-X11-lib
--without-X11-lib
--with-X11lib
--without-X11lib
--enable-tcl-h-ver-check
--disable-tcl-h-ver-check
--enable-tk-h-ver-check
--disable-tk-h-ver-check

Warning:: cannot find Tcl library. tcltklib will not be compiled (tcltklib is disabled on your Ruby. That is, Ruby/Tk will not work). Please check configure options.

Can't find proper Tcl/Tk libraries. So, can't make tcltklib.so which is required by Ruby/Tk.
If you have Tcl/Tk libraries on your environment, you may be able to use them with configure options (see ext/tk/README.tcltklib).
At present, Tcl/Tk8.6 is not supported. Although you can try to use Tcl/Tk8.6 with configure options, it will not work correctly. I recommend you to use Tcl/Tk8.5 or 8.4.

To see why this extension failed to compile, please check the mkmf.log which can be found here:

/var/lib/gems/2.7.0/extensions/x86_64-linux/2.7.0/tk-0.2.0/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /var/lib/gems/2.7.0/gems/tk-0.2.0 for inspection.
Results logged to /var/lib/gems/2.7.0/extensions/x86_64-linux/2.7.0/tk-0.2.0/gem_make.out

[jeremyevans]

You probably need the appropriate configuration options passed when installing the gem. What those options should be depend on your environment. For example, on OpenBSD, it is

gem install tk -- \
  --with-tcl-include=/usr/local/include/tcl8.5 \
  --with-tk-include=/usr/local/include/tk8.5 \
  --with-tcllib=tcl85 \
  --with-tklib=tk85 \
  --with-X11-dir=/usr/X11R6

Without knowing your environment, I'm not sure what options are appropriate for you.

[jeremyevans]

I'm going to close this now. Please try using the appropriate configure options for your environment. If you aren't sure what the options are, please include information on where the tcl/tk headers and shared libraries are installed, as well as their names.

[Nakilon]

Note: brew install tk would install 8.6 but you want 8.5 according to this gem notes.
To get 8.5 you should go to https://platform.activestate.com/fuckyouuu/ActiveTcl-8.5/distributions and register under some fake email (you don't want to trust this company because if you try to log in as Github they'll ask access to private repos -- another reason would be that it's a known issue in Github Auth API that they don't fix for years already but anyway).
After that the gem install tk completes with no issue.