[llvm-dev] Coverity Scan Needs to be Updated after GitHub Migration
Luke Benes via llvm-dev
Who has permission to change this?
_______________________________________________
LLVM Developers mailing list
llvm...@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
Luke Benes via llvm-dev
Whoever setup the original account, needs to change this. Or someone with admin permissions on github needs to create a new account? Who would I talk to about this?
Eli Friedman via llvm-dev
-Eli
Mehdi AMINI via llvm-dev
Sylvestre Ledru via llvm-dev
Hello,
The issue isn't about the repo configuration but more having a build working with cov-build. I stop carrying for two reasons:
* it was often regressing
* afaik, nobody but me was paying attention to newly detected defects (if I am wrong, please let me know and I can have a look).
By the way, I have been generating these reports:
https://llvm.org/reports/scan-build/
Cheers,
Sylvestre
Luke Benes via llvm-dev
> * afaik, nobody but me was paying attention to newly detected defects (if I am wrong, please let me know and I can have a look).
In my experience, a weekly report of new defects helps keep engagement up and issues down. Here is an example:
Would a weekly scan report be welcome here?
Mehdi AMINI via llvm-dev
Sylvestre Ledru via llvm-dev
https://scan.coverity.com/projects/llvm
Should run once a day.
Currently, it finds 3 048 defects in llvm, clang, lld, lldb, etc. Keep in mind that a bunch of them are false positive.
The component view broken currently (doesn't refresh with new configurations).
Screenshot of the kind of defect Coverity is identifying:
https://imgur.com/729Yrtp
Cheers,
Sylvestre
Le 02/06/2021 à 23:11, Mehdi AMINI a écrit :
> +Sylvestre Ledru <mailto:sylv...@debian.org> is the admin here.
>
> That said, I believe that anyone with admin permissions on the LLVM organization on Github can set up a new LLVM project on the coverity website.
>
>
> On Wed, Jun 2, 2021 at 12:53 PM Eli Friedman via llvm-dev <llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>> wrote:
>
> I doubt anyone on this mailing list has any control over the Coverity scan. I'd suggest emailing Coverity; it looks like the address is scan-...@coverity.com <mailto:scan-...@coverity.com> .
>
> -Eli
>
> -----Original Message-----
> From: llvm-dev <llvm-dev...@lists.llvm.org <mailto:llvm-dev...@lists.llvm.org>> On Behalf Of Luke Benes via llvm-dev
> Sent: Wednesday, June 2, 2021 12:14 PM
> To: llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>
> Subject: [EXT] Re: [llvm-dev] Coverity Scan Needs to be Updated after GitHub Migration
>
> As a reminder, the Coverity scan of the llvm project, https://scan.coverity.com/projects/llvm <https://scan.coverity.com/projects/llvm> is still pulling from the old subversion repository. It needs to be updated to https://github.com/llvm/llvm-project <https://github.com/llvm/llvm-project>.
>
> Whoever setup the original account, needs to change this. Or someone with admin permissions on github needs to create a new account? Who would I talk to about this?
>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev <https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
> _______________________________________________
> LLVM Developers mailing list
> llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev <https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
Sylvestre Ledru via llvm-dev
https://scan.coverity.com/projects/llvm
Should run once a day.
Currently, it finds 3 048 defects in llvm, clang, lld, lldb, etc. Keep in mind that a bunch of them are false positive.
The component view broken currently (doesn't refresh with new configurations).
Cheers,
Sylvestre
Le 02/06/2021 à 23:11, Mehdi AMINI a écrit :
> That said, I believe that anyone with admin permissions on the LLVM organization on Github can set up a new LLVM project on the coverity website.
>
>
>
> I doubt anyone on this mailing list has any control over the Coverity scan. I'd suggest emailing Coverity; it looks like the address is scan-...@coverity.com <mailto:scan-...@coverity.com> .
> -Eli
>
> -----Original Message-----
> From: llvm-dev <llvm-dev...@lists.llvm.org <mailto:llvm-dev...@lists.llvm.org>> On Behalf Of Luke Benes via llvm-dev
> Sent: Wednesday, June 2, 2021 12:14 PM
> To: llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>
> Subject: [EXT] Re: [llvm-dev] Coverity Scan Needs to be Updated after GitHub Migration
>
> Whoever setup the original account, needs to change this. Or someone with admin permissions on github needs to create a new account? Who would I talk to about this?
>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev <https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
> LLVM Developers mailing list
Sylvestre Ledru via llvm-dev
https://scan.coverity.com/projects/llvm
Should run once a day.
Currently, it finds 3 048 defects in llvm, clang, lld, lldb, etc. Keep in mind that a bunch of them are false positive.
The component view broken currently (doesn't refresh with new configurations).
https://imgur.com/729Yrtp
Cheers,
Sylvestre
Le 02/06/2021 à 23:11, Mehdi AMINI a écrit :
> That said, I believe that anyone with admin permissions on the LLVM organization on Github can set up a new LLVM project on the coverity website.
>
>
>
> I doubt anyone on this mailing list has any control over the Coverity scan. I'd suggest emailing Coverity; it looks like the address is scan-...@coverity.com <mailto:scan-...@coverity.com> .
> -Eli
>
> -----Original Message-----
> From: llvm-dev <llvm-dev...@lists.llvm.org <mailto:llvm-dev...@lists.llvm.org>> On Behalf Of Luke Benes via llvm-dev
> Sent: Wednesday, June 2, 2021 12:14 PM
> To: llvm...@lists.llvm.org <mailto:llvm...@lists.llvm.org>
> Subject: [EXT] Re: [llvm-dev] Coverity Scan Needs to be Updated after GitHub Migration
>
> Whoever setup the original account, needs to change this. Or someone with admin permissions on github needs to create a new account? Who would I talk to about this?
>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev <https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
> LLVM Developers mailing list
Luke Benes via llvm-dev
> Should run once a day.
Sylvester,
The report seems to be working perfectly. Thank you for taking the time to get this up and running again!
My only concern is that there is no visibly on these reports. Without the new issues being reported here, it is highly unlikely that they will get addressed.
Since there was interest and no objections, could you please add the [llvm-dev] list to the email?
You can do this by going to the "Project Settings" page:
https://scan.coverity.com/projects/llvm?tab=project_settings
"Additional Emails for New Defect Notifications"
-> llvm...@lists.llvm.org
Then could you please lower the report frequency to once or twice a week? With that we will receive weekly reports like this:
David Blaikie via llvm-dev
Mehdi AMINI via llvm-dev
Do the reports have deltas? (highlighting new defects with as fine revision granularity as possible) or do they only show the total set of findings at a given revision?
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
________________________________________________________________________________________________________
*** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
103 // Offset from the start of the containing input section.
104 uint32_t inSecOff;
105 uint32_t hash;
106 // Offset from the start of the containing output section.
107 uint64_t outSecOff;
108
>>> CID 1457502: Uninitialized members (UNINIT_CTOR)
>>> Non-static class member "outSecOff" is not initialized in this constructor nor in any functions that it calls.
109 StringPiece(uint64_t off, uint32_t hash) : inSecOff(off), hash(hash) {}
110 };
111
112 // CStringInputSections are composed of multiple null-terminated string
113 // literals, which we represent using StringPieces. These literals can be
114 // deduplicated and tail-merged, so translating offsets between the input and
** CID 1457501: Uninitialized members (UNINIT_CTOR)
/llvm/lib/ObjectYAML/XCOFFEmitter.cpp: 36 in <unnamed>::XCOFFWriter::XCOFFWriter(llvm::XCOFFYAML::Object &, llvm::raw_ostream &, llvm::function_ref<void (const llvm::Twine &)>)()
________________________________________________________________________________________________________
*** CID 1457501: Uninitialized members (UNINIT_CTOR)
/llvm/lib/ObjectYAML/XCOFFEmitter.cpp: 36 in <unnamed>::XCOFFWriter::XCOFFWriter(llvm::XCOFFYAML::Object &, llvm::raw_ostream &, llvm::function_ref<void (const llvm::Twine &)>)()
30
31 class XCOFFWriter {
32 public:
33 XCOFFWriter(XCOFFYAML::Object &Obj, raw_ostream &OS, yaml::ErrorHandler EH)
34 : Obj(Obj), W(OS, support::big), ErrHandler(EH) {
35 Is64Bit = Obj.Header.Magic == (llvm::yaml::Hex16)XCOFF::XCOFF64;
>>> CID 1457501: Uninitialized members (UNINIT_CTOR)
>>> Non-static class member "StartOffset" is not initialized in this constructor nor in any functions that it calls.
36 }
37 bool writeXCOFF();
38
39 private:
40 bool initFileHeader(uint64_t CurrentOffset);
41 bool initSectionHeader(uint64_t &CurrentOffset);
** CID 1457500: Incorrect expression (SIZEOF_MISMATCH)
/compiler-rt/lib/dfsan/dfsan_custom.cpp: 2367 in format_buffer(char *, unsigned long, const char *, unsigned char *, unsigned char *, unsigned int *, unsigned int *, __va_list_tag *)()
________________________________________________________________________________________________________
*** CID 1457500: Incorrect expression (SIZEOF_MISMATCH)
/compiler-rt/lib/dfsan/dfsan_custom.cpp: 2367 in format_buffer(char *, unsigned long, const char *, unsigned char *, unsigned char *, unsigned int *, unsigned int *, __va_list_tag *)()
2361 case 'n': {
2362 int *ptr = va_arg(ap, int *);
2363 *ptr = (int)formatter.str_off;
2364 va_labels++;
2365 if (va_origins)
2366 va_origins++;
>>> CID 1457500: Incorrect expression (SIZEOF_MISMATCH)
>>> Passing argument "ptr" of type "int *" and argument "8UL /* sizeof (ptr) */" to function "dfsan_set_label" is suspicious.
2367 dfsan_set_label(0, ptr, sizeof(ptr));
2368 end_fmt = true;
2369 break;
2370 }
2371
2372 case '%':
** CID 1457499: Incorrect expression (DIVIDE_BY_ZERO)
/llvm/lib/Analysis/CFGPrinter.cpp: 308 in llvm::DOTGraphTraits<llvm::DOTFuncInfo *>::isNodeHidden(const llvm::BasicBlock *, const llvm::DOTFuncInfo *)()
________________________________________________________________________________________________________
*** CID 1457499: Incorrect expression (DIVIDE_BY_ZERO)
/llvm/lib/Analysis/CFGPrinter.cpp: 308 in llvm::DOTGraphTraits<llvm::DOTFuncInfo *>::isNodeHidden(const llvm::BasicBlock *, const llvm::DOTFuncInfo *)()
302 const DOTFuncInfo *CFGInfo) {
303 if (HideColdPaths.getNumOccurrences() > 0)
304 if (auto *BFI = CFGInfo->getBFI()) {
305 uint64_t NodeFreq = BFI->getBlockFreq(Node).getFrequency();
306 uint64_t EntryFreq = BFI->getEntryFreq();
307 // Hide blocks with relative frequency below HideColdPaths threshold.
>>> CID 1457499: Incorrect expression (DIVIDE_BY_ZERO)
>>> In expression "(double)NodeFreq / EntryFreq", division by expression "EntryFreq" which may be zero has undefined behavior.
308 if ((double)NodeFreq / EntryFreq < HideColdPaths)
309 return true;
310 }
311 if (HideUnreachablePaths || HideDeoptimizePaths) {
312 if (isOnDeoptOrUnreachablePath.find(Node) ==
313 isOnDeoptOrUnreachablePath.end())
** CID 1457498: (DEADCODE)
/clang/lib/Sema/SemaDeclCXX.cpp: 11843 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
/clang/lib/Sema/SemaDeclCXX.cpp: 11789 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
________________________________________________________________________________________________________
*** CID 1457498: (DEADCODE)
/clang/lib/Sema/SemaDeclCXX.cpp: 11843 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
11837 return true;
11838 }
11839
11840 // No conflict between a tag and a non-tag.
11841 if (!NonTag) return false;
11842
>>> CID 1457498: (DEADCODE)
>>> Execution cannot reach this statement: "<temporary> = this->Diag(cl...".
11843 Diag(BUD->getLocation(), diag::err_using_decl_conflict);
11844 Diag(Target->getLocation(), diag::note_using_decl_target);
11845 Diag(NonTag->getLocation(), diag::note_using_decl_conflict);
11846 BUD->setInvalidDecl();
11847 return true;
11848 }
/clang/lib/Sema/SemaDeclCXX.cpp: 11789 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
11783 // Always emit a diagnostic for a mismatch between an unresolved
11784 // using_if_exists and a resolved using declaration in either direction.
11785 if (isa<UnresolvedUsingIfExistsDecl>(Target) !=
11786 (isa_and_nonnull<UnresolvedUsingIfExistsDecl>(NonTag))) {
11787 if (!NonTag && !Tag)
11788 return false;
>>> CID 1457498: (DEADCODE)
>>> Execution cannot reach this statement: "<temporary> = this->Diag(cl...".
11789 Diag(BUD->getLocation(), diag::err_using_decl_conflict);
11790 Diag(Target->getLocation(), diag::note_using_decl_target);
11791 Diag((NonTag ? NonTag : Tag)->getLocation(),
11792 diag::note_using_decl_conflict);
11793 BUD->setInvalidDecl();
11794 return true;
** CID 1457497: Integer handling issues (NEGATIVE_RETURNS)
________________________________________________________________________________________________________
*** CID 1457497: Integer handling issues (NEGATIVE_RETURNS)
/lld/MachO/InputSection.cpp: 117 in lld::macho::CStringInputSection::getStringPiece(unsigned long) const()
111 const StringPiece &CStringInputSection::getStringPiece(uint64_t off) const {
112 if (off >= data.size())
113 fatal(toString(this) + ": offset is outside the section");
114
115 auto it =
116 partition_point(pieces, [=](StringPiece p) { return p.inSecOff <= off; });
>>> CID 1457497: Integer handling issues (NEGATIVE_RETURNS)
>>> A negative constant "-1L" is passed as an argument to a parameter that cannot be negative.
117 return it[-1];
118 }
119
120 uint64_t CStringInputSection::getFileOffset(uint64_t off) const {
121 return parent->fileOff + getOffset(off);
122 }
** CID 1457496: Possible Control flow issues (DEADCODE)
/clang/lib/Sema/SemaDeclCXX.cpp: 11833 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
________________________________________________________________________________________________________
*** CID 1457496: Possible Control flow issues (DEADCODE)
/clang/lib/Sema/SemaDeclCXX.cpp: 11833 in clang::Sema::CheckUsingShadowDecl(clang::BaseUsingDecl *, clang::NamedDecl *, const clang::LookupResult &, clang::UsingShadowDecl *&)()
11827 // Target is not a function.
11828
11829 if (isa<TagDecl>(Target)) {
11830 // No conflict between a tag and a non-tag.
11831 if (!Tag) return false;
11832
>>> CID 1457496: Possible Control flow issues (DEADCODE)
>>> Execution cannot reach this statement: "<temporary> = this->Diag(cl...".
11833 Diag(BUD->getLocation(), diag::err_using_decl_conflict);
11834 Diag(Target->getLocation(), diag::note_using_decl_target);
11835 Diag(Tag->getLocation(), diag::note_using_decl_conflict);
11836 BUD->setInvalidDecl();
11837 return true;
11838 }
** CID 1419078: Resource leaks (VIRTUAL_DTOR)
/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp: 541 in ()
________________________________________________________________________________________________________
*** CID 1419078: Resource leaks (VIRTUAL_DTOR)
/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp: 541 in ()
535 return (Twine(Removed ? "-" : " ") + (InMST ? " " : "*") +
536 (IsCritical ? "c" : " ") + " W=" + Twine(Weight)).str();
537 }
538 };
539
540 // This class stores the auxiliary information for each BB.
>>> CID 1419078: Resource leaks (VIRTUAL_DTOR)
>>> Class "<unnamed>::BBInfo" does not have a virtual destructor.
541 struct BBInfo {
542 BBInfo *Group;
543 uint32_t Index;
544 uint32_t Rank = 0;
545
546 BBInfo(unsigned IX) : Group(this), Index(IX) {}
________________________________________________________________________________________________________
To view the defects in Coverity Scan visit, https://u15810271.ct.sendgrid.net/ls/click?upn=HRESupC-2F2Czv4BOaCWWCy7my0P0qcxCbhZ31OYv50yqtGMuad6pPsL7inW23sAqZCWZD0rQ5FZsyk18zSjnBpg-3D-3Dqen7_nlj59xHPRAo5NMSpMZh-2B1UYnQ4IBJNE2FCxtFGv5-2FfRZ2ZNTfin-2BJg3vqHM-2BrKWO-2BwAgQVf1GGFXh4xVX9UzXjq3jPiI59xzjIzanRxv0XSIVZFqDyJd-2BdQm4cXqcdS7Dt0L1fNQpWyw15e-2BbU4YMt1YpKZVa4kbM7Bjl6hGDatG6tnUuz5zUAdmlq-2B7z2QmYSc2DTghseWofWoq-2Bn7ssA-3D-3D
To manage Coverity Scan email notifications for "joke...@gmail.com", click https://u15810271.ct.sendgrid.net/ls/click?upn=HRESupC-2F2Czv4BOaCWWCy7my0P0qcxCbhZ31OYv50yped04pjJnmXOsUBtKYNIXxUrjVeIJ0Cfeziujhnhh3yxzc7w9MgExjQKEssnVrR9tYRoPYlaXXfdUjwRQLJCdFixsrT7mUhUA9ixc9DPUdquU2MMNgdrF247xaBicB0V4-3Dht-M_nlj59xHPRAo5NMSpMZh-2B1UYnQ4IBJNE2FCxtFGv5-2FfRZ2ZNTfin-2BJg3vqHM-2BrKWOP6G0-2FiydipnYxIKl-2Bk7AFFr9CcUjQXx7tq4qtWbpBdzz7-2Bib4DWeMAf-2Bv0hl9c0qiwYnDVi4C3uD0F0P9wRuATKCNq-2FJGcnjmQ51zJUZdom9QcwJ2QwYMBBjOk8G2ylW4oH3PujCpojyn5dsLN7qdQ-3D-3D
David Blaikie via llvm-dev
On Thu, Jun 10, 2021 at 10:20 AM David Blaikie via llvm-dev <llvm...@lists.llvm.org> wrote:Do the reports have deltas? (highlighting new defects with as fine revision granularity as possible) or do they only show the total set of findings at a given revision?Yes (see below sample email from today), which is why I'd prefer to keep this daily rather than weekly.
Ah, cool - thanks!
llvm-commits@ may be more suitable than llvm-dev@ for this?
Yeah, not sure. I don't feel too strongly either way.
From Coverity:
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
Is it easy for us to disable low-value findings (both on a per-instance, but also per-check-tye) basis in source (ie: without having to modify an external config)?
For instance, I'm not sure it's valuable for us to get notification on any member not initialized by a ctor. That could readily be detected by clang-tidy or clang warnings and we don't implement such checks in those places (which would be higher value because they can find the issue sooner rather than waiting for a long-running static analysis to come back with results).
Keeping the warnings low-noise would be really important (so whoever set this up or requested it I hope is really pushing to reduce the noise until nearly all results have pretty broad agreement that they should be fixed).
Tom Honermann via llvm-dev
On Thu, Jun 10, 2021 at 10:42 AM Mehdi AMINI <joke...@gmail.com> wrote:
From Coverity:
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
Is it easy for us to disable low-value findings (both on a per-instance, but also per-check-tye) basis in source (ie: without having to modify an external config)?
Source annotations are available for suppressing per-instance issues, but no source annotations are available to disable checkers entirely.
I don't see an option for disabling specific checkers in Coverity Scan. Checker enable/disable and tuning options are available when using a Coverity installation. I don't know why those capabilities wouldn't be exposed to Coverity Scan users.
For instance, I'm not sure it's valuable for us to get notification on any member not initialized by a ctor. That could readily be detected by clang-tidy or clang warnings and we don't implement such checks in those places (which would be higher value because they can find the issue sooner rather than waiting for a long-running static analysis to come back with results).
Keeping the warnings low-noise would be really important (so whoever set this up or requested it I hope is really pushing to reduce the noise until nearly all results have pretty broad agreement that they should be fixed).
Yes, the general deployment recommendation is to tune to minimize FPs and low value results and then relax such tuning as issues are addressed.
Tom.
Tom Honermann via llvm-dev
On 6/10/2021 2:54 PM, David Blaikie via llvm-dev wrote:
On Thu, Jun 10, 2021 at 10:42 AM Mehdi AMINI <joke...@gmail.com> wrote:
From Coverity:
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
Is it easy for us to disable low-value findings (both on a per-instance, but also per-check-tye) basis in source (ie: without having to modify an external config)?
Source annotations are available for suppressing per-instance issues, but no source annotations are available to disable checkers entirely.
I don't see an option for disabling specific checkers in Coverity Scan. Checker enable/disable and tuning options are available when using a Coverity installation. I don't know why those capabilities wouldn't be exposed to Coverity Scan users.
For instance, I'm not sure it's valuable for us to get notification on any member not initialized by a ctor. That could readily be detected by clang-tidy or clang warnings and we don't implement such checks in those places (which would be higher value because they can find the issue sooner rather than waiting for a long-running static analysis to come back with results).
I'm going to push back on this a bit. I've had to debug problems in Clang that turned out to be due to failure to initialize a data member. I find the number of uninitialized data member issues that Coverity reports on LLVM to be out of line with respect
to other projects I've seen scanned. I'm skeptical that omitting initializers has a significant impact on performance.
Coverity doesn't report every data member that isn't initialized by a member init; it looks for evidence that the data member is not initialized by any functions invoked by the constructor as well (whether in the same TU or not). It will therefore report
fewer FPs than either clang-tidy or clang warnings.
Tom.
David Blaikie via llvm-dev
On 6/11/2021 9:58 AM, Tom Honermann via llvm-dev wrote:
I confirmed with internal Coverity support that such options are not currently exposed to Coverity Scan users. Enhancement requests sent to scan-...@coverity.com will be considered for future Coverity Scan updates (I encourage sending an enhancement request).On 6/10/2021 2:54 PM, David Blaikie via llvm-dev wrote:
On Thu, Jun 10, 2021 at 10:42 AM Mehdi AMINI <joke...@gmail.com> wrote:
From Coverity:
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
Is it easy for us to disable low-value findings (both on a per-instance, but also per-check-tye) basis in source (ie: without having to modify an external config)?
Source annotations are available for suppressing per-instance issues, but no source annotations are available to disable checkers entirely.
I don't see an option for disabling specific checkers in Coverity Scan. Checker enable/disable and tuning options are available when using a Coverity installation. I don't know why those capabilities wouldn't be exposed to Coverity Scan users.
Having not setup the scanning/emails/etc I don't think I have enough context (I'm not exactly a "user" - at best I've read one email produced by the tool) to make a feature request.
For instance, I'm not sure it's valuable for us to get notification on any member not initialized by a ctor. That could readily be detected by clang-tidy or clang warnings and we don't implement such checks in those places (which would be higher value because they can find the issue sooner rather than waiting for a long-running static analysis to come back with results).
I'm going to push back on this a bit. I've had to debug problems in Clang that turned out to be due to failure to initialize a data member. I find the number of uninitialized data member issues that Coverity reports on LLVM to be out of line with respect to other projects I've seen scanned. I'm skeptical that omitting initializers has a significant impact on performance.
Tom Honermann via llvm-dev
On Fri, Jun 11, 2021 at 8:15 AM Tom Honermann <Thomas.H...@synopsys.com> wrote:
On 6/11/2021 9:58 AM, Tom Honermann via llvm-dev wrote:
I confirmed with internal Coverity support that such options are not currently exposed to Coverity Scan users. Enhancement requests sent to scan-...@coverity.com will be considered for future Coverity Scan updates (I encourage sending an enhancement request).On 6/10/2021 2:54 PM, David Blaikie via llvm-dev wrote:
On Thu, Jun 10, 2021 at 10:42 AM Mehdi AMINI <joke...@gmail.com> wrote:
From Coverity:
Please find the latest report on new defect(s) introduced to llvm found with Coverity Scan.
8 new defect(s) introduced to llvm found with Coverity Scan.
19 defect(s), reported by Coverity Scan earlier, were marked fixed in the recent build analyzed by Coverity Scan.
New defect(s) Reported-by: Coverity Scan
Showing 8 of 8 defect(s)
** CID 1457502: Uninitialized members (UNINIT_CTOR)
/lld/MachO/InputSection.h: 109 in lld::macho::StringPiece::StringPiece(unsigned long, unsigned int)()
Is it easy for us to disable low-value findings (both on a per-instance, but also per-check-tye) basis in source (ie: without having to modify an external config)?
Source annotations are available for suppressing per-instance issues, but no source annotations are available to disable checkers entirely.
I don't see an option for disabling specific checkers in Coverity Scan. Checker enable/disable and tuning options are available when using a Coverity installation. I don't know why those capabilities wouldn't be exposed to Coverity Scan users.
Having not setup the scanning/emails/etc I don't think I have enough context (I'm not exactly a "user" - at best I've read one email produced by the tool) to make a feature request.
For instance, I'm not sure it's valuable for us to get notification on any member not initialized by a ctor. That could readily be detected by clang-tidy or clang warnings and we don't implement such checks in those places (which would be higher value because they can find the issue sooner rather than waiting for a long-running static analysis to come back with results).
I'm going to push back on this a bit. I've had to debug problems in Clang that turned out to be due to failure to initialize a data member. I find the number of uninitialized data member issues that Coverity reports on LLVM to be out of line with respect to other projects I've seen scanned. I'm skeptical that omitting initializers has a significant impact on performance.
The tradeoff is that initializing values that aren't meant to be used reduces msan's ability to identify bugs if such a value is really used.
Yes, fair enough. Perhaps there is a way to provide a poisened initializer that is (effectively) elided when msan is enabled and used otherwise?
struct S {
int *p = POISON(nullptr);
};
Tom.