Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.c > #389541
| From | Ike Naar <ike@sdf.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: question about linker |
| Date | 2024-12-11 08:43 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <slrnvlik4j.ns4.ike@iceland.freeshell.org> (permalink) |
| References | (23 earlier) <vj1bss$325uo$1@dont-email.me> <vj1h4i$335q1$2@dont-email.me> <vj1mhi$34p7h$1@dont-email.me> <vj1prj$35je4$1@dont-email.me> <vj7dup$he7i$1@dont-email.me> |
On 2024-12-09, Janis Papanagnou <janis_papanagnou+ng@hotmail.com> wrote:
> An unambiguous grammar is something quite essential; how would you
> parse code if it were ambiguous?
Here's an ambiguity in the C grammar:
<statement>:
...
<selection-statement>
...
<selection-statement>:
...
if ( <expression> ) <statement>
if ( <expression> ) <statement> else <statement>
...
The following selection-statement is grammatically ambiguous:
if (E1) if (E2) S1 else S2
it has two possible parsings:
if (E1) <statement> else S2
where <statement> expands to
if (E2) S1
or
if (E1) <statement>
where <statement> expands to
if (E2) S1 else S2
The grammatical ambiguity is resolved by an additional rule in the
'Semantics' section for selection-statement:
3 An else is associated with the lexically nearest preceding if that is
allowed by the syntax.
gcc -Wall will issue a warning for such an ambiguous statement:
warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-07 12:34 +0100
Re: question about linker Bart <bc@freeuk.com> - 2024-12-07 13:04 +0000
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-07 15:36 +0100
Re: question about linker Bart <bc@freeuk.com> - 2024-12-07 15:33 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-07 13:38 -0800
Re: question about linker Bart <bc@freeuk.com> - 2024-12-07 22:47 +0000
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-09 19:46 +0100
Re: question about linker bart <bc@freeuk.com> - 2024-12-11 02:21 +0000
Re: question about linker antispam@fricas.org (Waldek Hebisch) - 2024-12-11 14:39 +0000
Re: question about linker bart <bc@freeuk.com> - 2024-12-11 15:34 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-11 14:06 -0800
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 00:02 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-11 16:42 -0800
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 01:14 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-11 17:27 -0800
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 11:48 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-12 12:50 -0800
goto considered helpful (Was: question about linker) Michael S <already5chosen@yahoo.com> - 2024-12-12 14:44 +0200
Re: goto considered helpful Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-12 13:50 -0800
Re: goto considered helpful Kaz Kylheku <643-408-1753@kylheku.com> - 2024-12-12 22:33 +0000
Re: goto considered helpful David Brown <david.brown@hesbynett.no> - 2024-12-13 09:50 +0100
Re: goto considered helpful bart <bc@freeuk.com> - 2024-12-13 11:12 +0000
Re: goto considered helpful Michael S <already5chosen@yahoo.com> - 2024-12-13 14:39 +0200
Re: goto considered helpful David Brown <david.brown@hesbynett.no> - 2024-12-13 14:31 +0100
Re: goto considered helpful David Brown <david.brown@hesbynett.no> - 2024-12-13 14:19 +0100
Re: goto considered helpful bart <bc@freeuk.com> - 2024-12-13 14:26 +0000
Re: goto considered helpful David Brown <david.brown@hesbynett.no> - 2024-12-13 17:52 +0100
Re: goto considered helpful Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-13 10:11 -0800
Re: goto considered helpful scott@slp53.sl.home (Scott Lurndal) - 2024-12-13 14:16 +0000
Re: goto considered helpful Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-13 14:50 +0100
Re: goto considered helpful (Was: question about linker) Rosario19 <Ros@invalid.invalid> - 2024-12-20 13:52 +0100
Re: goto considered helpful (Was: question about linker) Michael S <already5chosen@yahoo.com> - 2024-12-20 15:27 +0200
Re: goto considered helpful (Was: question about linker) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-12-24 09:05 -0800
Re: goto considered helpful (Was: question about linker) Rosario19 <Ros@invalid.invalid> - 2024-12-26 13:33 +0100
Re: goto considered helpful (Was: question about linker) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-12-28 09:29 -0800
Re: question about linker Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-12-12 06:54 -0800
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-11 17:24 +0100
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 12:11 +0000
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-12 15:56 +0100
Re: question about linker Ike Naar <ike@sdf.org> - 2024-12-11 08:43 +0000
Re: question about linker David Brown <david.brown@hesbynett.no> - 2024-12-11 16:28 +0100
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-11 17:46 +0100
Re: question about linker antispam@fricas.org (Waldek Hebisch) - 2024-12-12 02:31 +0000
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-11 17:30 +0100
Re: question about linker David Brown <david.brown@hesbynett.no> - 2024-12-11 17:47 +0100
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-11 17:51 +0100
Re: question about linker bart <bc@freeuk.com> - 2024-12-11 17:20 +0000
Re: question about linker David Brown <david.brown@hesbynett.no> - 2024-12-11 21:46 +0100
Re: question about linker bart <bc@freeuk.com> - 2024-12-11 21:19 +0000
Re: question about linker Michael S <already5chosen@yahoo.com> - 2024-12-12 00:03 +0200
Re: question about linker David Brown <david.brown@hesbynett.no> - 2024-12-12 11:08 +0100
Re: question about linker Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-12-23 16:02 -0800
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-12 05:50 +0100
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-11 21:35 -0800
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-12 12:38 +0100
Re: question about linker James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-12-18 16:04 -0500
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-19 01:35 +0100
Re: question about linker James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-12-19 06:39 -0500
Re: question about linker antispam@fricas.org (Waldek Hebisch) - 2024-12-19 14:58 +0000
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 12:29 +0000
Re: question about linker Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-12-12 07:01 -0800
Re: question about linker David Brown <david.brown@hesbynett.no> - 2024-12-11 21:36 +0100
Re: question about linker antispam@fricas.org (Waldek Hebisch) - 2024-12-11 13:59 +0000
Re: question about linker Bart <bc@freeuk.com> - 2024-12-07 14:57 +0000
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-07 16:19 +0100
Re: question about linker Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-12-07 16:28 +0100
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-07 13:44 -0800
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-07 13:58 -0800
Re: question about linker scott@slp53.sl.home (Scott Lurndal) - 2024-12-07 22:15 +0000
Re: question about linker antispam@fricas.org (Waldek Hebisch) - 2024-12-11 22:51 +0000
Re: question about linker Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-12-11 15:12 -0800
Re: question about linker bart <bc@freeuk.com> - 2024-12-12 00:52 +0000
csiph-web