# [PATCH] sparse: allow '{ 0 }' to be used without warnings 3 messages from 2020-05-21 to 2020-05-21. Participants: Luc Van Oostenryck, Eric Sunshine, Junio C Hamano. Thread: https://gitlist.dev/t/53530 ## Luc Van Oostenryck, 2020-05-21 21:45 Subject: [PATCH] sparse: allow '{ 0 }' to be used without warnings Message-ID: <20200521214544.8784-1-luc.vanoostenryck@gmail.com> URL: https://gitlist.dev/e/20200521214544.8784-1-luc.vanoostenryck%40gmail.com ``` In standard C, '{ 0 }' can be used as an universal zero-initializer. However, Sparse complains if this is used on a type where the first member (possibly nested) is a pointer since Sparse purposely wants to warn when '0' is used to initialize a pointer type. Legitimaly, it's desirable to be able to use '{ 0 }' as an idom without these warnings [1,2]. An option have now been added to Sparse to turn off such warnings. So, add this option to the SPARSE_FLAGS variable. [1] https://lore.kernel.org/r/e6796c60-a870-e761-3b07-b680f934c537@ramsayjones.plus.com [2] https://lore.kernel.org/r/xmqqd07xem9l.fsf@gitster.c.googlers.com Signed-off-by: Luc Van Oostenryck --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 3d3a39fc19..69f065ef8c 100644 --- a/Makefile +++ b/Makefile @@ -1189,7 +1189,7 @@ PTHREAD_CFLAGS = # For the 'sparse' target SPARSE_FLAGS ?= -SP_EXTRA_FLAGS = +SP_EXTRA_FLAGS = -Wno-universal-initializer # For the 'coccicheck' target; setting SPATCH_BATCH_SIZE higher will # usually result in less CPU usage at the cost of higher peak memory. -- 2.26.2 ``` ## Eric Sunshine, 2020-05-21 21:50 Subject: Re: [PATCH] sparse: allow '{ 0 }' to be used without warnings Message-ID: URL: https://gitlist.dev/e/CAPig%2BcQsYSE30ab9qQO7V%2BCzAdUodpw64sCnZH%2B1s3oD-P6msg%40mail.gmail.com In-Reply-To: <20200521214544.8784-1-luc.vanoostenryck@gmail.com> ``` On Thu, May 21, 2020 at 5:46 PM Luc Van Oostenryck wrote: > In standard C, '{ 0 }' can be used as an universal zero-initializer. > However, Sparse complains if this is used on a type where the first > member (possibly nested) is a pointer since Sparse purposely wants > to warn when '0' is used to initialize a pointer type. > > Legitimaly, it's desirable to be able to use '{ 0 }' as an idom > without these warnings [1,2]. s/idom/idiom/ > An option have now been added to Sparse to turn off such warnings. > So, add this option to the SPARSE_FLAGS variable. Do you have a reference to the commit or Sparse release notes which mention this new option? It might be nice to include it here in the commit message. Also, should this minimum Sparse version be mentioned somewhere in documentation so that people invoking the "sparse" makefile target aren't greeted with an error about -Wno-universal-initializer being an unrecognized option (assuming that older Sparse would complain about it)? > [1] https://lore.kernel.org/r/e6796c60-a870-e761-3b07-b680f934c537@ramsayjones.plus.com > [2] https://lore.kernel.org/r/xmqqd07xem9l.fsf@gitster.c.googlers.com > > Signed-off-by: Luc Van Oostenryck ``` ## Junio C Hamano, 2020-05-21 22:08 Subject: Re: [PATCH] sparse: allow '{ 0 }' to be used without warnings Message-ID: URL: https://gitlist.dev/e/xmqq4ks9rleu.fsf%40gitster.c.googlers.com In-Reply-To: ``` Eric Sunshine writes: > Do you have a reference to the commit or Sparse release notes which > mention this new option? It might be nice to include it here in the > commit message. Also, should this minimum Sparse version be mentioned > somewhere in documentation so that people invoking the "sparse" > makefile target aren't greeted with an error about > -Wno-universal-initializer being an unrecognized option (assuming that > older Sparse would complain about it)? Both sensible considerations. Thanks for bringing them up. > >> [1] https://lore.kernel.org/r/e6796c60-a870-e761-3b07-b680f934c537@ramsayjones.plus.com >> [2] https://lore.kernel.org/r/xmqqd07xem9l.fsf@gitster.c.googlers.com >> >> Signed-off-by: Luc Van Oostenryck ```