[PATCH] Fix clang-tidy delete of stack object

Alexander Kornienko alexfh at google.com
Fri Nov 14 10:32:59 PST 2014 

On Thu, Nov 13, 2014 at 6:39 PM, David Blaikie <dblaikie at gmail.com> wrote:

>
>
> On Thu, Nov 13, 2014 at 1:20 AM, Manuel Klimek <klimek at google.com> wrote:
>
>> +dblakie
>>
>> On Thu Nov 13 2014 at 1:53:39 AM Alexander Kornienko <alexfh at google.com>
>> wrote:
>>
>>> Thank you for the analysis and the proposed solution!
>>>
>>> I can reproduce the issue (with any q.cpp that is not clang-tidy clean):
>>>
>>> $ clang-tidy q.cpp -- --serialize-diagnostics test.dia
>>> *** Error in `clang_tidy': free(): invalid pointer: 0x00007fffa65bb4d8
>>> ***
>>> Aborted (core dumped)
>>>
>>>
>>> The patch seems correct to me and the way to distinguish between owning
>>> and non-owning constructors seems also fine. I'll commit the patch tomorrow
>>> if nobody offers a better solution.
>>>
>>
>> I don't really see anything better under the current restrictions.
>> Perhaps David has an idea, he has done a lot of the unique_ptr migrations
>> in llvm.
>>
>
> At a cursory glance, this is the "conditional ownership" issue that's come
> up in a few places (and currently we have solutions that both look like
> this one (T*+unique_ptr<T> where the latter may be null but otherwise they
> both point to the same object) or bool+T* where the bool indicates
> ownership)
>
> There is a thread on llvm/cfe-dev about whether we should introduce a
> reusable "conditional ownership" pointer, but the response from several
> people (Manuel, Chandler, and, depending on the day of the week, myself,
> etc) is that this kind of ownership complication is a bug in the design
> which we should fix at the source.
>
> I'm still not sure if that's the case (that all cases of conditional
> ownership like this are design bugs) - but I'm sort of curious to see how
> they would look if we really tried to apply that logic.
>
> As a side note: this patch looks way too subtle/dangerous as-is, even
> given the necessary conditional ownership semantics. Two branches of the
> if, one calls func(takeX()) the other calls func(unique_ptr<T>(takeX()) -
> that's pretty subtle (even though the "ownsClient" condition demonstrates
> what's going on there).
>
> I'm not sure how much it's worth making this a bit tidier/more reliable
> (maybe Diags::takeClient should return a unique_ptr and just return null
> whenever !Diags.ownsClient() - and have a separate "getClient" function
> that can be called to get a raw pointer, regardless of ownership (careful
> if we have an ordering issue there - if takeClient nulls out the Diags'
> client, then we'd need to call 'get' before 'take', if takeClient just sets
> "OwnsClient" to false, then we can call them in either order)) - or if it's
> just going to be a bit lame until we go the whole way and remove the
> conditional ownership of the DiagnosticConsumer all the way up (or add a
> first class maybe-owning pointer type).
>

Yeah, there are too many possible options here and ideally, it would be
nice to unify all cases of conditional ownership or eliminate them. I
suppose, that the latter may be rather difficult to make as the scope of
the change may be wide and affect many public interfaces. But in any case,
we need a centralized decision on what we want to do with the conditional
ownership.

As for this patch, it should use the already existing getClient() function
in the non-owning branch. I can commit a fix.


>
>
> - David
>
>
>>
>>
>>>
>>> -- Alex
>>>
>>> On Wed, Nov 12, 2014 at 9:32 PM, Aaron Wishnick <
>>> aaron.s.wishnick at gmail.com> wrote:
>>>
>>>> Understanding the bug better, I've attached a patch that more correctly
>>>> fixes this bug, by teaching ChainedDiagnosticConsumer how to not take
>>>> ownership of one of its arguments, and having SetupSerializedDiagnostics()
>>>> use it. Is there a more idiomatic way, in the LLVM project, of a "maybe"
>>>> owning pointer? I see that some related functions take a "ShouldOwnClient"
>>>> argument, but this seems a little more kludgy for two arguments with
>>>> separate ownership.
>>>>
>>>> Thanks,
>>>> Aaron
>>>>
>>>> On Wed, Nov 12, 2014 at 3:14 PM, Aaron Wishnick <
>>>> aaron.s.wishnick at gmail.com> wrote:
>>>>
>>>>> Hi Alexander, sorry to dig up an old issue, but I've just gotten some
>>>>> more time to look into it. This is still reproducing for me on trunk, and I
>>>>> can see where the ChainedDiagnosticConsumer is created, as well as why it
>>>>> ends up trying to free a stack object. In short, there's a function
>>>>> SetupSerializedDiagnostics() in CompilerInstance.cpp that doesn't know how
>>>>> to handle the case where its DiagnosticsEngine doesn't own its client. This
>>>>> bug can be reproduced by using clang-tidy with a compilation database that
>>>>> uses the "--serialize-diagnostics" flag.
>>>>>
>>>>> When I run a debug build with the arguments "clang-tidy -p
>>>>> /path/to/compile_commands.json /path/to/source.cpp", I get a failed assert
>>>>> in tools/clang/lib/Frontend/CompilerInstance.cpp, line 173, in
>>>>> SetupSerializedDiagnostics():
>>>>>
>>>>> static void SetupSerializedDiagnostics(DiagnosticOptions *DiagOpts,
>>>>>                                        DiagnosticsEngine &Diags,
>>>>>                                        StringRef OutputFile) {
>>>>>   auto SerializedConsumer =
>>>>>       clang::serialized_diags::create(OutputFile, DiagOpts);
>>>>>
>>>>>   assert(Diags.ownsClient());
>>>>>   Diags.setClient(new ChainedDiagnosticConsumer(
>>>>>       std::unique_ptr<DiagnosticConsumer>(Diags.takeClient()),
>>>>>       std::move(SerializedConsumer)));
>>>>> }
>>>>>
>>>>> Stepping one stack frame up into createDiagnostics(), it looks like
>>>>> this code path is hit because the "if
>>>>> (!Opts->DiagnosticSerializationFile.empty())" condition on line 209 of
>>>>> CompilerInstance.cpp is met.
>>>>>
>>>>> If I skip that assert, and continue, I get that same "pointer being
>>>>> freed was not allocated" error, once the program finishes and the
>>>>> ChainedDiagnosticConsumer is deleted. The address is from the stack, rather
>>>>> than the heap, and it corresponds to the value of "Diags.Client" before
>>>>> that call to "Diags.takeClient()." In other words, I think the problem is
>>>>> that the DiagnosticsEngine passed into SetupSerializedDiagnostics doesn't
>>>>> own its client, and the client is stack allocated, and then the client is
>>>>> stored in a unique_ptr which is owned by the ChainedDiagnosticConsumer.
>>>>>
>>>>> Ultimately, I can see this comes from ClangTidy.cpp, line 470. This
>>>>> ClangTidyDiagnosticConsumer is created on the stack, and is the one that
>>>>> eventually ends up being freed, causing the bug.
>>>>>
>>>>> I am using this in conjunction with Xcode: I am using xcodebuild to
>>>>> build my project, and then oclint-xcodebuild to generate the
>>>>> compile_commands.json database. Sure enough, all of the commands in the
>>>>> compilation database include the argument "--serialize-diagnostics
>>>>> /path/to/source.dia". If I remove these arguments, this bug doesn't occur.
>>>>> So, I think the issue is that SetupSerializedDiagnostics doesn't know how
>>>>> to handle the case where the DiagnosticsEngine doesn't own its client.
>>>>>
>>>>> Hope this helps!
>>>>>
>>>>> Best,
>>>>> Aaron
>>>>>
>>>>>
>>>>> On Mon, Jun 23, 2014 at 9:51 AM, Alexander Kornienko <
>>>>> alexfh at google.com> wrote:
>>>>>
>>>>>>
>>>>>> On Mon, Jun 23, 2014 at 2:51 PM, Alexander Kornienko <
>>>>>> alexfh at google.com> wrote:
>>>>>>
>>>>>>>
>>>>>>> On Thu, Jun 19, 2014 at 5:59 PM, Aaron Wishnick <
>>>>>>> aaron.s.wishnick at gmail.com> wrote:
>>>>>>>
>>>>>>>> When I run clang-tidy on OS X 10.9.3, I immediately get this output:
>>>>>>>>
>>>>>>>> clang-tidy(97903,0x7fff782fb310) malloc: *** error for object
>>>>>>>> 0x7fff5fbfecd0: pointer being freed was not allocated
>>>>>>>> *** set a breakpoint in malloc_error_break to debug
>>>>>>>>
>>>>>>>> This occurs inside the destructor of ClangTidyDiagnosticConsumer.
>>>>>>>> Here's my callstack:
>>>>>>>>
>>>>>>>> #4 0x000000010058e3e2 in ~ClangTidyDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/ClangTidyDiagnosticConsumer.h:190
>>>>>>>> #5 0x0000000100656a73 in
>>>>>>>> std::__1::default_delete<clang::DiagnosticConsumer>::operator()(clang::DiagnosticConsumer*)
>>>>>>>> const [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2426
>>>>>>>> #6 0x0000000100656a4b in
>>>>>>>> std::__1::unique_ptr<clang::DiagnosticConsumer,
>>>>>>>> std::__1::default_delete<clang::DiagnosticConsumer>
>>>>>>>> >::reset(clang::DiagnosticConsumer*) [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2625
>>>>>>>> #7 0x00000001006569f5 in ~unique_ptr [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2593
>>>>>>>> #8 0x00000001006569f5 in ~unique_ptr [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2593
>>>>>>>> #9 0x00000001006569f5 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #10 0x0000000100656595 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #11 0x00000001006565b9 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #12 0x00000001015eec84 in ~DiagnosticsEngine at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Basic/Diagnostic.cpp:68
>>>>>>>> #13 0x00000001015eec35 in ~DiagnosticsEngine at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Basic/Diagnostic.cpp:66
>>>>>>>> #14 0x00000001006bd3d3 in
>>>>>>>> llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:55
>>>>>>>> #15 0x00000001006bd325 in
>>>>>>>> llvm::IntrusiveRefCntPtrInfo<clang::DiagnosticsEngine>::release(clang::DiagnosticsEngine*)
>>>>>>>> at /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:90
>>>>>>>> #16 0x00000001006bd2fd in
>>>>>>>> llvm::IntrusiveRefCntPtr<clang::DiagnosticsEngine>::release() at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:199
>>>>>>>> #17 0x00000001006bd2c5 in ~IntrusiveRefCntPtr at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:172
>>>>>>>> #18 0x00000001006bbe15 in ~IntrusiveRefCntPtr at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:172
>>>>>>>> #19 0x000000010065cbc1 in ~CompilerInstance at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:63
>>>>>>>> #20 0x000000010065c505 in ~CompilerInstance at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:61
>>>>>>>> #21 0x00000001005d6474 in
>>>>>>>> clang::tooling::FrontendActionFactory::runInvocation(clang::CompilerInvocation*,
>>>>>>>> clang::FileManager*, clang::DiagnosticConsumer*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:270
>>>>>>>> #22 0x00000001005d614f in
>>>>>>>> clang::tooling::ToolInvocation::runInvocation(char const*,
>>>>>>>> clang::driver::Compilation*, clang::CompilerInvocation*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:243
>>>>>>>> #23 0x00000001005d5290 in clang::tooling::ToolInvocation::run() at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:229
>>>>>>>> #24 0x00000001005d7b29 in
>>>>>>>> clang::tooling::ClangTool::run(clang::tooling::ToolAction*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:360
>>>>>>>> #25 0x0000000100566cd2 in
>>>>>>>> clang::tidy::runClangTidy(clang::tidy::ClangTidyOptionsProvider*,
>>>>>>>> clang::tooling::CompilationDatabase const&,
>>>>>>>> llvm::ArrayRef<std::__1::basic_string<char, std::__1::char_traits<char>,
>>>>>>>> std::__1::allocator<char> > >,
>>>>>>>> std::__1::vector<clang::tidy::ClangTidyError,
>>>>>>>> std::__1::allocator<clang::tidy::ClangTidyError> >*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/ClangTidy.cpp:345
>>>>>>>> #26 0x0000000100002a96 in main at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/tool/ClangTidyMain.cpp:145
>>>>>>>>
>>>>>>>> In short, it appears that ClangTool takes ownership of the
>>>>>>>> diagnostic consumer, but it's being allocated on the stack. My fix is to
>>>>>>>> allocate it on the heap instead. I've attached my patch. Please let me know
>>>>>>>> if this assessment is incorrect, or if you'd like me to go about this
>>>>>>>> differently.
>>>>>>>>
>>>>>>>
>>>>>>> Well, the ownership of the diagnostic consumer shouldn't be
>>>>>>> transferred, and I don't see any evidence ClangTool::setDiagnosticConsumer
>>>>>>> expects this to happen. This all looks strange, and I'm investigating this.
>>>>>>>
>>>>>>
>>>>>> I wasn't able to reproduce this crash. Your stack trace has
>>>>>> ChainedDiagnosticConsumer in it, which afaiu, it is only used twice in
>>>>>> Clang, and both places don't seem to be unrelated to clang-tidy. Could you
>>>>>> set a breakpoint in ChainedDiagnosticConsumer constructor and send me the
>>>>>> stack trace where it gets called in clang-tidy? (or add an "assert(false);"
>>>>>> there to get the stack trace on the console in the assertions-enabled build)
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> Thanks!
>>>>>>>> Aaron
>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> cfe-commits mailing list
>>>>>>>> cfe-commits at cs.uiuc.edu
>>>>>>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>>>>>>>
>>>>>>>
>>>>>
>>>>> On Mon, Jun 23, 2014 at 9:51 AM, Alexander Kornienko <
>>>>> alexfh at google.com> wrote:
>>>>>
>>>>>>
>>>>>> On Mon, Jun 23, 2014 at 2:51 PM, Alexander Kornienko <
>>>>>> alexfh at google.com> wrote:
>>>>>>
>>>>>>>
>>>>>>> On Thu, Jun 19, 2014 at 5:59 PM, Aaron Wishnick <
>>>>>>> aaron.s.wishnick at gmail.com> wrote:
>>>>>>>
>>>>>>>> When I run clang-tidy on OS X 10.9.3, I immediately get this output:
>>>>>>>>
>>>>>>>> clang-tidy(97903,0x7fff782fb310) malloc: *** error for object
>>>>>>>> 0x7fff5fbfecd0: pointer being freed was not allocated
>>>>>>>> *** set a breakpoint in malloc_error_break to debug
>>>>>>>>
>>>>>>>> This occurs inside the destructor of ClangTidyDiagnosticConsumer.
>>>>>>>> Here's my callstack:
>>>>>>>>
>>>>>>>> #4 0x000000010058e3e2 in ~ClangTidyDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/ClangTidyDiagnosticConsumer.h:190
>>>>>>>> #5 0x0000000100656a73 in
>>>>>>>> std::__1::default_delete<clang::DiagnosticConsumer>::operator()(clang::DiagnosticConsumer*)
>>>>>>>> const [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2426
>>>>>>>> #6 0x0000000100656a4b in
>>>>>>>> std::__1::unique_ptr<clang::DiagnosticConsumer,
>>>>>>>> std::__1::default_delete<clang::DiagnosticConsumer>
>>>>>>>> >::reset(clang::DiagnosticConsumer*) [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2625
>>>>>>>> #7 0x00000001006569f5 in ~unique_ptr [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2593
>>>>>>>> #8 0x00000001006569f5 in ~unique_ptr [inlined] at
>>>>>>>> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/memory:2593
>>>>>>>> #9 0x00000001006569f5 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #10 0x0000000100656595 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #11 0x00000001006565b9 in ~ChainedDiagnosticConsumer at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/include/clang/Frontend/ChainedDiagnosticConsumer.h:23
>>>>>>>> #12 0x00000001015eec84 in ~DiagnosticsEngine at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Basic/Diagnostic.cpp:68
>>>>>>>> #13 0x00000001015eec35 in ~DiagnosticsEngine at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Basic/Diagnostic.cpp:66
>>>>>>>> #14 0x00000001006bd3d3 in
>>>>>>>> llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:55
>>>>>>>> #15 0x00000001006bd325 in
>>>>>>>> llvm::IntrusiveRefCntPtrInfo<clang::DiagnosticsEngine>::release(clang::DiagnosticsEngine*)
>>>>>>>> at /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:90
>>>>>>>> #16 0x00000001006bd2fd in
>>>>>>>> llvm::IntrusiveRefCntPtr<clang::DiagnosticsEngine>::release() at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:199
>>>>>>>> #17 0x00000001006bd2c5 in ~IntrusiveRefCntPtr at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:172
>>>>>>>> #18 0x00000001006bbe15 in ~IntrusiveRefCntPtr at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:172
>>>>>>>> #19 0x000000010065cbc1 in ~CompilerInstance at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:63
>>>>>>>> #20 0x000000010065c505 in ~CompilerInstance at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:61
>>>>>>>> #21 0x00000001005d6474 in
>>>>>>>> clang::tooling::FrontendActionFactory::runInvocation(clang::CompilerInvocation*,
>>>>>>>> clang::FileManager*, clang::DiagnosticConsumer*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:270
>>>>>>>> #22 0x00000001005d614f in
>>>>>>>> clang::tooling::ToolInvocation::runInvocation(char const*,
>>>>>>>> clang::driver::Compilation*, clang::CompilerInvocation*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:243
>>>>>>>> #23 0x00000001005d5290 in clang::tooling::ToolInvocation::run() at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:229
>>>>>>>> #24 0x00000001005d7b29 in
>>>>>>>> clang::tooling::ClangTool::run(clang::tooling::ToolAction*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/lib/Tooling/Tooling.cpp:360
>>>>>>>> #25 0x0000000100566cd2 in
>>>>>>>> clang::tidy::runClangTidy(clang::tidy::ClangTidyOptionsProvider*,
>>>>>>>> clang::tooling::CompilationDatabase const&,
>>>>>>>> llvm::ArrayRef<std::__1::basic_string<char, std::__1::char_traits<char>,
>>>>>>>> std::__1::allocator<char> > >,
>>>>>>>> std::__1::vector<clang::tidy::ClangTidyError,
>>>>>>>> std::__1::allocator<clang::tidy::ClangTidyError> >*) at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/ClangTidy.cpp:345
>>>>>>>> #26 0x0000000100002a96 in main at
>>>>>>>> /Users/awishnick/clang-tidy/llvm/tools/clang/tools/extra/clang-tidy/tool/ClangTidyMain.cpp:145
>>>>>>>>
>>>>>>>> In short, it appears that ClangTool takes ownership of the
>>>>>>>> diagnostic consumer, but it's being allocated on the stack. My fix is to
>>>>>>>> allocate it on the heap instead. I've attached my patch. Please let me know
>>>>>>>> if this assessment is incorrect, or if you'd like me to go about this
>>>>>>>> differently.
>>>>>>>>
>>>>>>>
>>>>>>> Well, the ownership of the diagnostic consumer shouldn't be
>>>>>>> transferred, and I don't see any evidence ClangTool::setDiagnosticConsumer
>>>>>>> expects this to happen. This all looks strange, and I'm investigating this.
>>>>>>>
>>>>>>
>>>>>> I wasn't able to reproduce this crash. Your stack trace has
>>>>>> ChainedDiagnosticConsumer in it, which afaiu, it is only used twice in
>>>>>> Clang, and both places don't seem to be unrelated to clang-tidy. Could you
>>>>>> set a breakpoint in ChainedDiagnosticConsumer constructor and send me the
>>>>>> stack trace where it gets called in clang-tidy? (or add an "assert(false);"
>>>>>> there to get the stack trace on the console in the assertions-enabled build)
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> Thanks!
>>>>>>>> Aaron
>>>>>>>>
>>>>>>>>  _______________________________________________
>>> cfe-commits mailing list
>>> cfe-commits at cs.uiuc.edu
>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>>>
>>
>
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