Re: MAKECMDGOALS and spaces

[Kaz Kylheku (gmake)]

On 2021-02-13 13:13, Christof Warlich wrote:
> Kaz Kylheku wrote:
>
> > I think to make use of this, you need to define a target that has
> > a space. It seems this is possible as follows
> >
> >
> >   hi\ ho:
> >   [tab]echo yes
> >
> > Then make "hi ho" runs the recipe and "yes" is echoed.
> >
> > In order to do this with a generated rule from $(MAKECMDGOALS),
> > you would need some way to do the expansion such that the
> > spaces are similarly escaped.
> The problem is that replacing every space with an escaped space only
> works as long as MAKECMDGOALS consists of one goal only: If more goals
> are given on the command line, their separating space would be replaced
> as well, as the distinction between target separating spaces and
> in-target spaces obviously get lost in MAKECMDGOALS.
>
> Thus, I'm pretty sure that there is no generic way to do what I was
> asking for, but I just want to double-check in case I'm missing 
> something.

The problem is that the value of a GNU  Make variable is just a "char *" 
string.

When main.c adds targets to the MAKECMDGOALS variable, it's just this:

      {
        /* Add this target name to the MAKECMDGOALS variable. */
        struct variable *gv;
        const char *value;

        gv = lookup_variable (STRING_SIZE_TUPLE ("MAKECMDGOALS"));
        if (gv == 0)
          value = f->name;
        else
          {
            /* Paste the old and new values together */
            size_t oldlen, newlen;
            char *vp;

            oldlen = strlen (gv->value);
            newlen = strlen (f->name);
            vp = alloca (oldlen + 1 + newlen + 1);
            memcpy (vp, gv->value, oldlen);
            vp[oldlen] = ' ';
            memcpy (&vp[oldlen + 1], f->name, newlen + 1);
            value = vp;
          }
        define_variable_cname ("MAKECMDGOALS", value, o_default, 0);
      }
    }


"Add a space followed by the datum to a stack-allocated copy of the 
variable,
then install the result as a replacement of the variable."

MAKECMDGOALS does not have the information required to recover targets
with spaces.