Re: [Cython] [cython-users] "Stack" checker for undefined behaviour in C code
On 31 October 2013 20:25, Stefan Behnel wrote: > Hi, > > I just came across this paper: > > http://pdos.csail.mit.edu/~xi/papers/stack-sosp13.pdf > > They describe an analysis tool that checks C code for bugs that exploit > undefined behaviour and that are thus up to the mercy of compiler > assumptions and "optimisations" to do the right thing or not. They made it > available on github: > > https://github.com/xiw/stack/ > > If anyone wants to take the time to set it up for checking some Cython > generated code, I'd be interested to see if it finds something. > I tested with mpi4py and got 0 warnings. I'll run it on Cython's testsuite. -- Lisandro Dalcin --- CIMEC (UNL/CONICET) Predio CONICET-Santa Fe Colectora RN 168 Km 472, Paraje El Pozo 3000 Santa Fe, Argentina Tel: +54-342-4511594 (ext 1016) Tel/Fax: +54-342-4511169 ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
[Cython] Files with executable bit on
This is in branch 0.19.x. These files should not have the executable bit on. Can any of you please fix them? [dalcinl@macarena cython-dev]$ ls -al $(find Cython -name '*.py') | grep rwx -rwxr-xr-x 1 dalcinl staff4286 Feb 14 2013 Cython/Build/BuildExecutable.py -rwxr-xr-x 1 dalcinl staff 420289 Oct 15 23:39 Cython/Compiler/ExprNodes.py -rwxr-xr-x 1 dalcinl staff 137439 Oct 15 23:39 Cython/Compiler/PyrexTypes.py -- Lisandro Dalcin --- CIMEC (UNL/CONICET) Predio CONICET-Santa Fe Colectora RN 168 Km 472, Paraje El Pozo 3000 Santa Fe, Argentina Tel: +54-342-4511594 (ext 1016) Tel/Fax: +54-342-4511169 ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
Re: [Cython] [cython-users] "Stack" checker for undefined behaviour in C code
On 1 November 2013 15:55, Lisandro Dalcin wrote: > On 31 October 2013 20:25, Stefan Behnel wrote: >> Hi, >> >> I just came across this paper: >> >> http://pdos.csail.mit.edu/~xi/papers/stack-sosp13.pdf >> >> They describe an analysis tool that checks C code for bugs that exploit >> undefined behaviour and that are thus up to the mercy of compiler >> assumptions and "optimisations" to do the right thing or not. They made it >> available on github: >> >> https://github.com/xiw/stack/ >> >> If anyone wants to take the time to set it up for checking some Cython >> generated code, I'd be interested to see if it finds something. >> > > I tested with mpi4py and got 0 warnings. I'll run it on Cython's testsuite. > > I got two warnings out of 'python setup.py build' Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.17387.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Plex/Actions.17412.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Runtime/refnanny.17706.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Code.17659.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.17614.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Lexicon.17437.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Visitor.17577.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Scanning.17462.ll Analyzing ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Parsing.17489.ll Generated 2 warnings, see pstack.txt for details. [dalcinl@kw2060 build.bak]$ cat pstack.txt --- bug: anti-dce model: | %523 = icmp ne i64 %522, 0, !dbg !1139 --> false : %518 = load %struct._object** @PyExc_UnboundLocalError, align 8, !dbg !1140 %519 = call %struct._object* (%struct._object*, i8*, ...)* @PyErr_Format(%struct._object* %518, i8* getelementptr inbounds ([49 x i8]* @.str100, i32 0, i32 0), i8* getelementptr inbounds ([6 x i8]* @.str52, i32 0, i32 0)), !dbg !1140 br label %605, !dbg !1143 stack: - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:6651:0 - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:1752:0 ncore: 1 core: - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:6511:0 - null pointer dereference --- bug: anti-simplify model: | %7699 = icmp ne %struct._object* %78, null, !dbg !4455 --> true stack: - /home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.c:16304:0 ncore: 1 core: - /home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.c:30198:0 - null pointer dereference -- Lisandro Dalcin --- CIMEC (UNL/CONICET) Predio CONICET-Santa Fe Colectora RN 168 Km 472, Paraje El Pozo 3000 Santa Fe, Argentina Tel: +54-342-4511594 (ext 1016) Tel/Fax: +54-342-4511169 ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
Re: [Cython] Files with executable bit on
Done. On Fri, Nov 1, 2013 at 6:16 AM, Lisandro Dalcin wrote: > This is in branch 0.19.x. These files should not have the executable > bit on. Can any of you please fix them? > > [dalcinl@macarena cython-dev]$ ls -al $(find Cython -name '*.py') | grep rwx > -rwxr-xr-x 1 dalcinl staff4286 Feb 14 2013 > Cython/Build/BuildExecutable.py > -rwxr-xr-x 1 dalcinl staff 420289 Oct 15 23:39 Cython/Compiler/ExprNodes.py > -rwxr-xr-x 1 dalcinl staff 137439 Oct 15 23:39 > Cython/Compiler/PyrexTypes.py > > -- > Lisandro Dalcin > --- > CIMEC (UNL/CONICET) > Predio CONICET-Santa Fe > Colectora RN 168 Km 472, Paraje El Pozo > 3000 Santa Fe, Argentina > Tel: +54-342-4511594 (ext 1016) > Tel/Fax: +54-342-4511169 > ___ > cython-devel mailing list > cython-devel@python.org > https://mail.python.org/mailman/listinfo/cython-devel ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
Re: [Cython] [cython-users] "Stack" checker for undefined behaviour in C code
Lisandro Dalcin, 01.11.2013 14:52: > On 1 November 2013 15:55, Lisandro Dalcin wrote: >> On 31 October 2013 20:25, Stefan Behnel wrote: >>> I just came across this paper: >>> >>> http://pdos.csail.mit.edu/~xi/papers/stack-sosp13.pdf >>> >>> They describe an analysis tool that checks C code for bugs that exploit >>> undefined behaviour and that are thus up to the mercy of compiler >>> assumptions and "optimisations" to do the right thing or not. They made it >>> available on github: >>> >>> https://github.com/xiw/stack/ >>> >>> If anyone wants to take the time to set it up for checking some Cython >>> generated code, I'd be interested to see if it finds something. >> >> I tested with mpi4py and got 0 warnings. I'll run it on Cython's testsuite. > > I got two warnings out of 'python setup.py build' Thanks for testing! > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.17387.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Plex/Actions.17412.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Runtime/refnanny.17706.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Code.17659.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.17614.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Lexicon.17437.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Visitor.17577.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Scanning.17462.ll > Analyzing > ./build/temp.linux-x86_64-2.7/home/dalcinl/Devel/cython-dev/Cython/Compiler/Parsing.17489.ll > Generated 2 warnings, see pstack.txt for details. > [dalcinl@kw2060 build.bak]$ cat pstack.txt > --- > bug: anti-dce > model: | > %523 = icmp ne i64 %522, 0, !dbg !1139 > --> false > > : > %518 = load %struct._object** @PyExc_UnboundLocalError, align 8, !dbg !1140 > %519 = call %struct._object* (%struct._object*, i8*, ...)* > @PyErr_Format(%struct._object* %518, i8* getelementptr inbounds ([49 x > i8]* @.str100, i32 0, i32 0), i8* getelementptr inbounds ([6 x i8]* > @.str52, i32 0, i32 0)), !dbg !1140 > br label %605, !dbg !1143 > stack: > - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:6651:0 > - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:1752:0 > ncore: 1 > core: > - /home/dalcinl/Devel/cython-dev/Cython/Plex/Scanners.c:6511:0 > - null pointer dereference > --- > bug: anti-simplify > model: | > %7699 = icmp ne %struct._object* %78, null, !dbg !4455 > --> true > stack: > - /home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.c:16304:0 > ncore: 1 > core: > - /home/dalcinl/Devel/cython-dev/Cython/Compiler/FlowControl.c:30198:0 > - null pointer dereference Erm - interesting. I looked through the code lines above and couldn't find anything that looked suspicious. I hope I used the same source version as you did (latest master?). Maybe I was just blinded by macros, but what I saw looked rather reasonable... Stefan ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
Re: [Cython] [cython-users] "Stack" checker for undefined behaviour in C code
On 1 November 2013 21:53, Stefan Behnel wrote: > > Erm - interesting. I looked through the code lines above and couldn't find > anything that looked suspicious. I hope I used the same source version as > you did (latest master?). Maybe I was just blinded by macros, but what I > saw looked rather reasonable... > Oh! Sorry, I've used branch 0.19.x, I'll check master and report back my findings. -- Lisandro Dalcin --- CIMEC (UNL/CONICET) Predio CONICET-Santa Fe Colectora RN 168 Km 472, Paraje El Pozo 3000 Santa Fe, Argentina Tel: +54-342-4511594 (ext 1016) Tel/Fax: +54-342-4511169 ___ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
