Bug 389373

Summary: exp-sgcheck the 'impossible' happened as Ist_LoadG is not instrumented
Product: [Developer tools] valgrind Reporter: Olivier Huber <oli.huber>
Component: sgcheckAssignee: Julian Seward <jseward>
Status: RESOLVED FIXED    
Severity: normal CC: philippe.waroquiers
Priority: NOR    
Version First Reported In: 3.13.0   
Target Milestone: ---   
Platform: Gentoo Packages   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: exp-sgcheck verbose output

Description Olivier Huber 2018-01-24 16:28:28 UTC 
Created attachment 110094 [details]
exp-sgcheck verbose output

First of all, thanks for maintaining/developing valgrind, such a great tool!

I tried for the first time to use the sgcheck tool, but the tool cannot run my (any?) executable. The error is 

exp-sgcheck: sg_main.c:2332 (sg_instrument_IRStmt): the 'impossible' happened.

This issue has been reported on the mailing-list earlier this months. Someone gave instructions to provide more debugging info:

https://www.mail-archive.com/valgrind-users@lists.sourceforge.net/msg06477.html

I attached the output of the second command, that is

valgrind --tool=exp-sgcheck --trace-flags=11000000 --trace-notbelow=1564 /bin/ls


Some additional info:

$ uname -a
Linux fenchel 4.14.14-gentoo #1 SMP PREEMPT Sun Jan 21 17:22:28 CST 2018 x86_64 Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz GenuineIntel GNU/Linux

The binary have been compiled with gcc-7.2.0. The system is using glibc 2.26
Comment 1 Philippe Waroquiers 2018-03-11 15:01:10 UTC 
(should be) fixed in 88a591de86e76864249a6e21adbf32774b0695bf
(at least, it now does something to instrument Ist_LoadG.

I guess we will one day or another encounter a crash due to Ist_StoreG :)