Why does mc throw an error when entering a directory with a space in the name?

Question

linux

All this is done on the command line of the running mc.
I create a directory with a space in the name:
# mkdir '/tmp/test test2'
Creates normally. I'm trying to go into it:
# cd '/tmp/test test2'
mc throws out a red window with a message that the directory was not found. If you go to it by pressing 'enter' on the directory will display the message "Warning: cannot change to /tmp/test test2", but the directory's table of contents will show you can copy and delete files - from the panels. When trying to execute any command through the command line, the command is ignored, thrown into the top-level directory.
wtf?
mc 4.8.19, ext4

# uname -a
Linux geobase0 4.4.39-calculate #1 SMP PREEMPT Fri Jan 13 13:45:12 UTC 2017 x86_64 Intel(R) Core(TM) i7-5960X CPU @ 3.00GHz GenuineIntel GNU/Linux

UPD: This all happens if the login-shell is tcsh, if the login-shell is bash, no error occurs. Because tcsh is somehow specially processed in subshell.c, why is not clear yet.

Answer 1

And so:
cd /tmp/test\ test2

Answer 2

It's getting weirder and weirder...
This fucking message is issued by the following code:

if (bPathNotEq && mc_global.shell->type == SHELL_TCSH)
        {
            char rp_subshell_cwd[PATH_MAX];
            char rp_current_panel_cwd[PATH_MAX];
            char *p_subshell_cwd, *p_current_panel_cwd;

            p_subshell_cwd = mc_realpath (subshell_cwd, rp_subshell_cwd);
            p_current_panel_cwd = mc_realpath (pcwd, rp_current_panel_cwd);

            if (p_subshell_cwd == NULL)
                p_subshell_cwd = subshell_cwd;
            if (p_current_panel_cwd == NULL)
                p_current_panel_cwd = pcwd;
            bPathNotEq = strcmp (p_subshell_cwd, p_current_panel_cwd) != 0;
        }

        if (bPathNotEq && !DIR_IS_DOT (pcwd))
        {
            char *cwd;

            cwd =
                vfs_path_to_str_flags (subshell_get_cwd_from_current_panel (), 0,
                                       VPF_STRIP_PASSWORD);
            vfs_print_message (_("Warning: Cannot change to %s.\n"), cwd);
            g_free (cwd);
        }

Here, subshell_cwd is filled with a call to feed_subshell() and pcwd is filled with a call to subshell_get_cwd_from_current_panel(). The first contains the wrong value, the second is correct. Naturally, the condition works and bamts. subshell_cwd in feed_subshell() is populated via standard read():
And here I've blunted so far - if mc is launched from tcsh, then read, having found the name of the directory with a space, reads up to the nearest slash! . If from bash - reads exactly as much as necessary. wtf?