On 09/14/17 03:20, Zeng, Star wrote: > Seemingly, VS has similar issue with GCC. > > VS2010/VS2012 still have the building failures below after this patch. :( > edk2\mdemodulepkg\universal\disk\udfdxe\filesystemoperations.c(1083) : error > C2220: warning treated as error - no 'executable' file generated > edk2\mdemodulepkg\universal\disk\udfdxe\filesystemoperations.c(1083) : > warning C4701: potentially uninitialized local variable 'FilePosition' used > edk2\mdemodulepkg\universal\disk\udfdxe\filesystemoperations.c(1078) : > warning C4701: potentially uninitialized local variable 'FinishedSeeking' used > edk2\mdemodulepkg\universal\disk\udfdxe\filesystemoperations.c(1167) : > warning C4701: potentially uninitialized local variable 'Data' used > edk2\mdemodulepkg\universal\disk\udfdxe\filesystemoperations.c(1167) : > warning C4703: potentially uninitialized local pointer variable 'Data' used > > > Liming, Dandan and Hao, > Do you remember how we fix this kind of false alarm before? > Just initialize the variable at the beginning of the function?
I think that all such warnings should be evaluated carefully. Can you please file a TianoCore BZ about the above? Paulo might want to take a look. Thanks! Laszlo > -----Original Message----- > From: Zeng, Star > Sent: Thursday, September 14, 2017 8:43 AM > To: Ard Biesheuvel <[email protected]>; Laszlo Ersek > <[email protected]> > Cc: Ni, Ruiyu <[email protected]>; Dong, Eric <[email protected]>; > edk2-devel-01 <[email protected]>; Gao, Liming <[email protected]>; > Zeng, Star <[email protected]> > Subject: RE: [edk2] [PATCH 2/2] MdeModulePkg/UdfDxe: suppress incorrect > compiler warning in ReadFile() > > Comparing adding workaround in code with suppressing it in *OLD* version > GCCs, I prefer the latter personally. > > > Thanks, > Star > -----Original Message----- > From: edk2-devel [mailto:[email protected]] On Behalf Of Ard > Biesheuvel > Sent: Thursday, September 14, 2017 2:52 AM > To: Laszlo Ersek <[email protected]> > Cc: Ni, Ruiyu <[email protected]>; Dong, Eric <[email protected]>; > edk2-devel-01 <[email protected]>; Gao, Liming <[email protected]>; > Zeng, Star <[email protected]> > Subject: Re: [edk2] [PATCH 2/2] MdeModulePkg/UdfDxe: suppress incorrect > compiler warning in ReadFile() > > On 13 September 2017 at 11:49, Laszlo Ersek <[email protected]> wrote: >> On 09/13/17 08:43, Zeng, Star wrote: >>> Beyond the Rb (I do not want to block this patch series), I am curious >>> about one question. >>> >>> There may be more this kind of workarounds to fix the build failure. >>> Is it possible to disable the warning (like below example for VS) for >>> specific version of GCC for this kind of false alarm? >>> >>> >>> ProcessorBind.h: >>> #if defined(_MSC_EXTENSIONS) >>> >>> ... >>> >>> #if _MSC_VER == 1800 || _MSC_VER == 1900 >>> >>> // >>> // Disable these warnings for VS2013. >>> // >>> >>> // >>> // This warning is for potentially uninitialized local variable, and >>> it may cause false // positive issues in VS2013 and VS2015 build // >>> #pragma warning ( disable : 4701 ) >>> >>> // >>> // This warning is for potentially uninitialized local pointer >>> variable, and it may cause // false positive issues in VS2013 and >>> VS2015 build // #pragma warning ( disable : 4703 ) >>> >>> #endif >>> >>> #endif >> >> I think starting with gcc-4.6, gcc supports the "diagnostics" pragma, >> which can be used to suppress warnings. >> >> Unfortunately, there's no pragma to suppress *only* the incorrect >> warnings :) So if we set the pragma, we could lose even those warnings >> that point out real bugs. >> > > That applies to the VS case as well. But I think doing this for older GCCs is > fine, most EDK2 developers use a newer version anyway, so we will not lose > any coverage by doing so. > _______________________________________________ > edk2-devel mailing list > [email protected] > https://lists.01.org/mailman/listinfo/edk2-devel > _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
