Re: linux-next: disabling -Wstringop-truncation
Hi Stephen, Andi, (Linus), On Fri, Aug 31, 2018 at 3:17 AM, Linus Torvalds wrote: > On Thu, Aug 30, 2018 at 3:07 PM Stephen Rothwell > wrote: >> >> I am now mainly using gcc v8.2 for my builds and -Wstringop-truncation >> causes so many warnings that I am sure to miss others, so I have >> applied the below to my fixes tree until the noise reduces. > > Applied. > > If people want the warning with W=xyz, then this is still the correct > patch, and we should add a line to re-enable it in > scripts/Makefile.extrawarn. For reference, I am sending the v5 of the Compiler Attributes series with the __nonstring patches appended on top, and I am adding the warning back as well, on W=1. I think W=1 is better: there are not that many warnings compared to those in W=2. AFAIK, it is relatively easy to achieve a clean W=1 (and most code should at least try be W=1 clean, no?). Also, note that now people can use __nonstring to suppress that warning (if applicable); and that using properly __nonstring can detect even more problems (i.e. adding __nonstring may trigger additional warnings, e.g. -Wstringop-overflow); so I think we should encourage the use of __nonstring. Cheers, Miguel
Re: linux-next: disabling -Wstringop-truncation
On Thu, Aug 30, 2018 at 3:07 PM Stephen Rothwell wrote: > > I am now mainly using gcc v8.2 for my builds and -Wstringop-truncation > causes so many warnings that I am sure to miss others, so I have > applied the below to my fixes tree until the noise reduces. Applied. If people want the warning with W=xyz, then this is still the correct patch, and we should add a line to re-enable it in scripts/Makefile.extrawarn. Linus
Re: linux-next: disabling -Wstringop-truncation
Hi Andi, On Thu, 30 Aug 2018 15:32:06 -0700 Andi Kleen wrote: > > Stephen Rothwell writes: > > > I am now mainly using gcc v8.2 for my builds and -Wstringop-truncation > > causes so many warnings that I am sure to miss others, so I have > > applied the below to my fixes tree until the noise reduces. > > I have the same problem. > > However It's not clear if they're all false positives (I suspect not) Right. > It would be better to move the warning to W=2 or so, and also needs > someone actually looking at them. Sure, my patch was just a quick fix for linux-next to make it more manageable. Also, I am not worse off than when I was using older compilers. -- Cheers, Stephen Rothwell pgpX_5y4c5siH.pgp Description: OpenPGP digital signature
Re: linux-next: disabling -Wstringop-truncation
Stephen Rothwell writes: > Hi Linus, > > I am now mainly using gcc v8.2 for my builds and -Wstringop-truncation > causes so many warnings that I am sure to miss others, so I have > applied the below to my fixes tree until the noise reduces. I have the same problem. However It's not clear if they're all false positives (I suspect not) It would be better to move the warning to W=2 or so, and also needs someone actually looking at them. -Andi
linux-next: disabling -Wstringop-truncation
Hi Linus, I am now mainly using gcc v8.2 for my builds and -Wstringop-truncation causes so many warnings that I am sure to miss others, so I have applied the below to my fixes tree until the noise reduces. From: Stephen Rothwell Date: Fri, 31 Aug 2018 07:47:28 +1000 Subject: [PATCH] disable stringop truncation warnings for now They are too noisy Signed-off-by: Stephen Rothwell --- Makefile | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Makefile b/Makefile index 2b458801ba74..a34a9283ee90 100644 --- a/Makefile +++ b/Makefile @@ -807,6 +807,9 @@ KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,) # disable pointer signed / unsigned warnings in gcc 4.0 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign) +# disable stringop warnings in gcc 8+ +KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation) + # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) -- 2.19.0.rc1 -- Cheers, Stephen Rothwell pgpE6H6wykfAB.pgp Description: OpenPGP digital signature
