Bug#507173: indent: adds extra const keywords to C++ programs (fwd)

[Santiago Vila]

Hello.

I received this from the Debian bug system.
There is a proposed patch at the end.

---------- Forwarded message ----------
From: Timo Juhani Lindfors <address@hidden>
To: Debian Bug Tracking System <address@hidden>
Date: Fri, 28 Nov 2008 20:49:35 +0200
Subject: Bug#507173: indent: adds extra const keywords to C++ programs

Package: indent
Version: 2.2.10-1
Severity: normal

Steps to reproduce:
1) cat > svg.cc <<EOF
void Svg::write(std::ostream &st, const Graph &g) const { }
EOF
2) indent -o svg.cc.indent svg.cc

Expected results:
2) svg.cc.indent and svg.cc differ only in whitespace

Actual results:
2) svg.cc.indent has extra const keyword:

void
Svg::write (std::ostream & st, const Graph & g) const const
{
}


More info:
1) If I run indent again to the output file it adds yet another const
keyword. This means that indent is not idempotent and can not be used
to check whether a file already has correct indentation or not.
2) The bug also occurs with indent 2.2.9-7 in debian stable.
3) It seems that the first const is written by handle_token_decl() and
the second const is written by copy_id():


case decl:
    /* we have a declaration type (int, register, etc.) */

    handle_token_decl(dec_ind, file_exit_value,
                      pbreak_line);

    copy_id(type_code, force_nl, file_exit_value, can_break);

Maybe this could be fixed by just not writing const from
handle_token_decl?

-----------------------------------------------------------
Later, Erwin Burgstaller <address@hidden> writes:

I've found this patch and it's working:


--- indent.c.orig       Tue Jan 31 18:00:29 2006
+++ indent.c    Sat Sep  2 12:48:07 2006
@@ -1439,6 +1439,7 @@
     {
         char           * t_ptr;
         set_buf_break (bb_const_qualifier, paren_target);
+#if 0  /* fix doubling of C++ tokens */
         *e_code++ = ' ';

         for (t_ptr = token; t_ptr < token_end; ++t_ptr)
@@ -1448,6 +1449,7 @@
         }

         *e_code = '\0';     /* null terminate code sect */
+#endif /* fix doubling of C++ tokens */
     }
     else
     {