[libcxx] r222052 - Initialize pointer in string conversion helpers to prevent MSAN diagnostic.

[Evgeniy Stepanov]

Should be fixed in r223650.

On Wed Nov 19 2014 at 1:23:42 PM Evgeniy Stepanov <eugenis at google.com>
wrote:

> On Wed Nov 19 2014 at 3:54:46 AM Eric Fiselier <eric at efcs.ca> wrote:
>
>> It seems you are missing interceptors for wcstof, wcstod, and wcstold as
>> well.
>>
>> Could this be responsible for PR21579 as well?
>> http://llvm.org/bugs/show_bug.cgi?id=21579
>>
>
> Unlikely.
>
>
>>
>>
>> /Eric
>>
>> On Tue, Nov 18, 2014 at 2:44 AM, Evgeniy Stepanov <eugenis at google.com>
>> wrote:
>>
>>> We are missing interceptors for: wcstol, wcstoul, wcstoll, wcstoull.
>>>
>>> On Mon Nov 17 2014 at 11:02:13 PM Kostya Serebryany <kcc at google.com>
>>> wrote:
>>>
>>>> if msan does not see what's goign on inside libc we need to teach it --
>>>> it already has a bunch of libc interceptors, but clearly not all.
>>>> Do you know what libc function is called here?
>>>> Or how to reproduce the reports you've been seeing?
>>>>
>>>> On Fri, Nov 14, 2014 at 2:23 PM, Eric Fiselier <eric at efcs.ca> wrote:
>>>>
>>>>> Author: ericwf
>>>>> Date: Fri Nov 14 16:23:57 2014
>>>>> New Revision: 222052
>>>>>
>>>>> URL: http://llvm.org/viewvc/llvm-project?rev=222052&view=rev
>>>>> Log:
>>>>> Initialize pointer in string conversion helpers to prevent MSAN
>>>>> diagnostic.
>>>>>
>>>>> Since the initialization of the pointer happens across the libc
>>>>> library boundry
>>>>> MSAN will not know the pointer was initialized. This fixes MSAN
>>>>> failures in
>>>>> test/strings/string.conversions.
>>>>>
>>>>> Modified:
>>>>>     libcxx/trunk/src/string.cpp
>>>>>
>>>>> Modified: libcxx/trunk/src/string.cpp
>>>>> URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/
>>>>> string.cpp?rev=222052&r1=222051&r2=222052&view=diff
>>>>> ============================================================
>>>>> ==================
>>>>> --- libcxx/trunk/src/string.cpp (original)
>>>>> +++ libcxx/trunk/src/string.cpp Fri Nov 14 16:23:57 2014
>>>>> @@ -63,7 +63,7 @@ inline
>>>>>  V
>>>>>  as_integer_helper(const string& func, const S& str, size_t* idx, int
>>>>> base, F f)
>>>>>  {
>>>>> -    typename S::value_type* ptr;
>>>>> +    typename S::value_type* ptr = nullptr;
>>>>>      const typename S::value_type* const p = str.c_str();
>>>>>      typename remove_reference<decltype(errno)>::type errno_save =
>>>>> errno;
>>>>>      errno = 0;
>>>>> @@ -180,7 +180,7 @@ inline
>>>>>  V
>>>>>  as_float_helper(const string& func, const S& str, size_t* idx, F f )
>>>>>  {
>>>>> -    typename S::value_type* ptr;
>>>>> +    typename S::value_type* ptr = nullptr;
>>>>>      const typename S::value_type* const p = str.c_str();
>>>>>      typename remove_reference<decltype(errno)>::type errno_save =
>>>>> errno;
>>>>>      errno = 0;
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> cfe-commits mailing list
>>>>> cfe-commits at cs.uiuc.edu
>>>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>>>>>
>>>>
>>>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20141208/4abf8482/attachment.html>