[lug] A head scratcher for your weekend

[Lee Woodworth]

Can all of the libs referenced by libQt5Core be loaded as a non-root user?

$ ldd /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10.1
$ ldd /usr/lib/x86_64-linux-gnu/libQt5Core.so.5

If these all succeed with no missing libs that narrows down the issue to
loading from the executable.

Do you have other qt-based binaries that work?

A long shot, but have you rebooted after the qt upgrades?
On other distros, I have had weird issues after qt updates that
were resolved by a reboot.

On 05/21/2018 05:34 AM, Matt Bidwell wrote:
> It appears to stat it many times. Here's the last one:
> stat("/lib/x86_64-linux-gnu", {st_mode=S_IFDIR|0755, st_size=16384, ...}) = 0
> openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libQt5Core.so.5", O_RDONLY|O_CLOEXEC) = 3
> read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 at g\t\0\0\0\0\0"..., 832) = 832
> lseek(3, 5167904, SEEK_SET)             = 5167904
> read(3, "\4\0\0\0\20\0\0\0\1\0\0\0GNU\0\0\0\0\0\3\0\0\0\21\0\0\0\0\0\0\0", 32) = 32
> close(3)                                = 0
> 
> Here's wht ldconfig -p get's me.
> # ldconfig -p | grep libQt5Core.so.5
>      libQt5Core.so.5 (libc6,x86-64, OS ABI: Linux 3.17.0) => 
> /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
> 
> I really do appreciate the help. There were some Qt package updates this morning including 
> libqt5core5a. Updating them didn't fix anything but I may dig through the change logs 
> later. -Matt
> 
> On 05/20/2018 08:30 PM, Davide Del Vento wrote:
>> In the strace output, is there any attempt to load any of the
>> /usr/lib/x86_64-linux-gnu/libQt5Core.so.5* ?
>> If so, you should get the clue we're after.
>> If not, that's the weirdness, especially if it shows (succeeding)
>> attempts to load /usr/lib/x86_64-linux-gnu/libQt5Script.so.5 as the
>> ldd suggests.
>>
>> On Sun, May 20, 2018 at 6:49 PM, Zan Lynx <zlynx at acm.org> wrote:
>>> On 5/20/2018 4:46 PM, Matt Bidwell wrote:
>>>>
>>>> openat(AT_FDCWD, "/usr/lib/libQt5Core.so.5", O_RDONLY|O_CLOEXEC) = 3
>>>
>>>
>>> This one is not in the 64-bit library location so it is rejected for loading
>>> into a 64-bit program. At least if it is following the usual Linux
>>> distribution file locations.
>>>
>>> -- 
>>>                  Knowledge is Power -- Power Corrupts
>>>                          Study Hard -- Be Evil
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> 
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