Re: [PATCH 0/2] fail compilation with strcpy
Jeff King writes: > I suspect it has more to do with system/libc differences between our > machines, anyway. There was discussion elsewhere in the thread about the > need to #undef before redefining. I guess this answers that question. Yes, that is it. For now I can squash this in before pushing it out on 'pu'. banned.h | 6 ++ 1 file changed, 6 insertions(+) diff --git a/banned.h b/banned.h index ae64a9..d138f3ecf2 100644 --- a/banned.h +++ b/banned.h @@ -10,11 +10,17 @@ #define BANNED(func) sorry_##func##_is_a_banned_function() +#undef strcpy #define strcpy(x,y) BANNED(strcpy) + +#undef strncpy #define strncpy(x,y,n) BANNED(strncpy) #ifdef HAVE_VARIADIC_MACROS + +#undef sprintf #define sprintf(...) BANNED(sprintf) + #endif #endif /* BANNED_H */
Re: [PATCH 0/2] fail compilation with strcpy
On Fri, Jul 20, 2018 at 11:58:10AM -0700, Junio C Hamano wrote: > > Note that this needs to be applied on top of 022d2ac1f3 (blame: prefer > > xsnprintf to strcpy for colors, 2018-07-13) or it will complain loudly. :) > > > > [1/2]: introduce "banned function" list > > [2/2]: banned.h: mark strncpy as banned > > Hmph, there is no use of any banned function in hex.c, but when > this topic is merged to 'pu', I seem to get this: Interesting. Builds fine for me even merged to the latest push-out of pu. But... > $ make DEVELOPER=1 hex.o > GIT_VERSION = 2.18.0.758.g18f90b35b8 > CC hex.o > In file included from git-compat-util.h:1250:0, > from cache.h:4, > from hex.c:1: > banned.h:14:0: error: "strncpy" redefined [-Werror] > #define strncpy(x,y,n) BANNED(strncpy) > > In file included from /usr/include/string.h:630:0, > from git-compat-util.h:165, > from cache.h:4, > from hex.c:1: > /usr/include/x86_64-linux-gnu/bits/string2.h:84:0: note: this is the location > of the previous definition > # define strncpy(dest, src, n) __builtin_strncpy (dest, src, n) I suspect it has more to do with system/libc differences between our machines, anyway. There was discussion elsewhere in the thread about the need to #undef before redefining. I guess this answers that question. I'll include that in the re-roll, and you can just ignore the v1 patches I sent for now. -Peff
Re: [PATCH 0/2] fail compilation with strcpy
Jeff King writes: > This is a patch series to address the discussion in the thread at: > > https://public-inbox.org/git/20180713204350.ga16...@sigill.intra.peff.net/ > > Basically, the question was: can we declare strcpy banned and have a > linter save us the trouble of finding it in review. The answer is yes, > the compiler is good at that. ;) > > There are probably as many lists of banned functions as there are coding > style documents. I don't agree with every entry in the ones I've seen. > And in many cases coccinelle is a better choice, because the problem is > not "this function is so bad your patch should not even make it to the > list with it", but "don't do it like A; we prefer to do it like B > instead". And coccinelle does the latter more flexibly and > automatically. > > So I tried to pick some obvious and uncontroversial candidates here. > gets() could be another one, but it's mostly banned already (it's out of > the standard, and most libcs mark it with a deprecated attribute). > > Note that this needs to be applied on top of 022d2ac1f3 (blame: prefer > xsnprintf to strcpy for colors, 2018-07-13) or it will complain loudly. :) > > [1/2]: introduce "banned function" list > [2/2]: banned.h: mark strncpy as banned Hmph, there is no use of any banned function in hex.c, but when this topic is merged to 'pu', I seem to get this: $ make DEVELOPER=1 hex.o GIT_VERSION = 2.18.0.758.g18f90b35b8 CC hex.o In file included from git-compat-util.h:1250:0, from cache.h:4, from hex.c:1: banned.h:14:0: error: "strncpy" redefined [-Werror] #define strncpy(x,y,n) BANNED(strncpy) In file included from /usr/include/string.h:630:0, from git-compat-util.h:165, from cache.h:4, from hex.c:1: /usr/include/x86_64-linux-gnu/bits/string2.h:84:0: note: this is the location of the previous definition # define strncpy(dest, src, n) __builtin_strncpy (dest, src, n) cc1: all warnings being treated as errors Makefile:2279: recipe for target 'hex.o' failed make: *** [hex.o] Error 1
[PATCH 0/2] fail compilation with strcpy
This is a patch series to address the discussion in the thread at: https://public-inbox.org/git/20180713204350.ga16...@sigill.intra.peff.net/ Basically, the question was: can we declare strcpy banned and have a linter save us the trouble of finding it in review. The answer is yes, the compiler is good at that. ;) There are probably as many lists of banned functions as there are coding style documents. I don't agree with every entry in the ones I've seen. And in many cases coccinelle is a better choice, because the problem is not "this function is so bad your patch should not even make it to the list with it", but "don't do it like A; we prefer to do it like B instead". And coccinelle does the latter more flexibly and automatically. So I tried to pick some obvious and uncontroversial candidates here. gets() could be another one, but it's mostly banned already (it's out of the standard, and most libcs mark it with a deprecated attribute). Note that this needs to be applied on top of 022d2ac1f3 (blame: prefer xsnprintf to strcpy for colors, 2018-07-13) or it will complain loudly. :) [1/2]: introduce "banned function" list [2/2]: banned.h: mark strncpy as banned Documentation/CodingGuidelines | 3 +++ banned.h | 20 git-compat-util.h | 2 ++ 3 files changed, 25 insertions(+) create mode 100644 banned.h -Peff
