Re: RFA: c-lang.c -vs- \0

Andrew Cagney
2002-09-17T05:29:35Z

> This is an updated version of my \0-printing patch.
>
> In double-quoted strings we now print \0 as "\000" to avoid ambiguity.
> In single-quoted output we still print '\0'.
>
> There is also a test suite patch enclosed. I didn't add a new test,
> as this functionality is already adequately tested. However, I did
> update the existing tests to reflect the new output.
>
> Tested with no regressions on x86 Red Hat Linux 7.3.
> As usual, built with the usual warnings enabled and -Werror.
>
> Ok to commit?
>
> Tom
>
> Index: ChangeLog
> from Tom Tromey <tromey@redhat.com>
>
> * c-lang.c (c_emit_char): Don't treat \0 specially unless quoter
> is "'".

Yes, but ...

> Index: c-lang.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/c-lang.c,v
> retrieving revision 1.13
> diff -u -r1.13 c-lang.c
> --- c-lang.c 11 Jul 2002 13:50:49 -0000 1.13
> +++ c-lang.c 14 Sep 2002 19:57:11 -0000
> @@ -78,9 +78,13 @@
> case '\007':
> fputs_filtered ("\\a", stream);
> break;
> - case '\0':
> - fputs_filtered ("\\0", stream);
> - break;
> + case '\0':
> + if (quoter == '\'')
> + {
> + fputs_filtered ("\\0", stream);
> + break;
> + }
> + /* Fall through. */

without the fallthrough. Just clone the line below. (Need to get
-Wswitch-fallthrough working :-).

The testcase, can then go in as well as ``obvious''.

Andrew

> default:
> fprintf_filtered (stream, "\\%.3o", (unsigned int) c);
> break;
> Index: testsuite/ChangeLog
> from Tom Tromey <tromey@redhat.com>
>
> * gdb.base/printcmds.exp (test_print_string_constants): Expect
> \000, not \0, in double-quoted string.
>
> Index: testsuite/gdb.base/printcmds.exp
> ===================================================================
> RCS file: /cvs/src/src/gdb/testsuite/gdb.base/printcmds.exp,v
> retrieving revision 1.9
> diff -u -r1.9 printcmds.exp
> --- testsuite/gdb.base/printcmds.exp 10 May 2002 20:25:26 -0000 1.9
> +++ testsuite/gdb.base/printcmds.exp 14 Sep 2002 19:57:21 -0000
> @@ -620,7 +620,7 @@
> set timeout 60;
>
> gdb_test "p \"a string\"" " = \"a string\""
> - gdb_test "p \"embedded \\000 null\"" " = \"embedded \\\\0 null\""
> + gdb_test "p \"embedded \\000 null\"" " = \"embedded \\\\000 null\""
> gdb_test "p \"abcd\"\[2\]" " = 99 'c'"
> gdb_test "p sizeof (\"abcdef\")" " = 7"
> gdb_test "ptype \"foo\"" " = char \\\[4\\\]"
>