Re: gawk: "please file a bug report"

[arnold]

Hi.

W.R.T. this:

J Naman <jnaman2@gmail.com> wrote:

> Sorry, just exploring in dark corridors ... gsub() *target*: @strong regex.
> Feel free to use/not use this in a future gawk_source\gawk-master\test
> -john naman gawker@703n.com
>
> gawk: C:\Nsoft\@nsLib\dev\TESTquickRgxGsub.Tr2.awk:8: warning: typeof
> detected invalid flags combination `MALLOC|STRING|STRCUR|NUMCUR|REGEX';
> please file a bug report.
>
> BEGIN{
> print "Initialize strong regex"
> rgx2=rgx1=@/[abc]/
> printf("rgx%d='%s'\ttypeof(rgx%d)='%s'\n",1,rgx1,1,typeof(rgx1));
> printf("rgx%d='%s'\ttypeof(rgx%d)='%s'\n",2,rgx2,2,typeof(rgx2));
> print "Test gsub() a strong regex"
> gsub(/b/,"e",rgx2);
> printf("rgx%d='%s'\ttypeof(rgx%d)='%s'\n",1,rgx1,1,typeof(rgx1));   #< line
> 8 warning
> printf("rgx%d='%s'\ttypeof(rgx%d)='%s'\n",2,rgx2,2,typeof(rgx2));
> }
> #========================================
> Stdout:
> Initialize strong regex
> rgx1='[abc]' typeof(rgx1)='regexp'
> rgx2='[abc]' typeof(rgx2)='regexp'
> Test gsub() a strong regex
> rgx1='[abc]' typeof(rgx1)='unknown'        #< line 8 warning
> rgx2='[aec]' typeof(rgx2)='string'
> #-----------------------------------------

Here is the patch.

Thanks,

Arnold
-------------------------------------------------------
diff --git a/builtin.c b/builtin.c
index 454034f4..e1ba5eb3 100644
--- a/builtin.c
+++ b/builtin.c
@@ -2934,8 +2934,6 @@ do_sub(int nargs, unsigned int flags)
                        RESTART(rp, target->stptr) > target->stlen)
                goto done;
 
-       target->flags |= STRING;
-
        text = target->stptr;
        textlen = target->stlen;
 
@@ -3183,6 +3181,10 @@ done:
                        DEREF(target);
                        assert(buf != NULL);
                        return make_str_node(buf, textlen, ALREADY_MALLOCED);
+               } else if ((target->flags & STRING) == 0) {
+                       /* return a copy of original string */
+                       DEREF(target);
+                       return make_str_node(target->stptr, target->stlen, 0);
                }
 
                /* return the original string */
@@ -3193,8 +3195,34 @@ done:
        if ((flags & LITERAL) != 0)
                DEREF(target);
        else if (matches > 0) {
-               unref(*lhs);
-               *lhs = make_str_node(buf, textlen, ALREADY_MALLOCED);
+               /*
+                * 8/2021: There's a bit of a song and dance here.  If someone 
does
+                *
+                *      x = @/abc/
+                *      sub(/b/, "x", x)
+                *
+                * What should the type of x be after the call? Does it get 
converted
+                * to string? Or does it remain a regexp?  We've decided to let 
it
+                * remain a regexp. In that case, we have to update the compiled
+                * regular expression that it holds.
+                */
+               bool is_regex = false;
+               NODE *target = *lhs;
+
+               if ((target->flags & REGEX) != 0) {
+                       is_regex = true;
+
+                       // free old regex registers
+                       refree(target->typed_re->re_reg[0]);
+                       if (target->typed_re->re_reg[1] != NULL)
+                               refree(target->typed_re->re_reg[1]);
+                       freenode(target->typed_re);
+               }
+               unref(*lhs);            // nuke original value
+               if (is_regex)
+                       *lhs = make_typed_regex(buf, textlen);
+               else
+                       *lhs = make_str_node(buf, textlen, ALREADY_MALLOCED);
        }
 
        return make_number((AWKNUM) matches);