search for: funwind

There’s this bug: https://bugs.llvm.org/show_bug.cgi?id=38468. I’ve managed to track it down to a configuration issue. The thing is that in order for libunwind to be usable on ARM Linux, it should be built with the -funwind-tables flag. This flag is conditionally set here: https://github.com/llvm/llvm-project/blob/master/libunwind/CMakeLists.txt#L294, if the compiler “supports” it. However, the CMake check fails with the following error: ``` ld.lld: error: undefined symbol: __aeabi_unwind_cpp_pr0 >>> refer...

I recently debugged an issue where I wasn't getting stack traces from ASAN on 32-bit ARM (on Android) when using a libclang_rt.asan-arm-android.so I'd built myself. I finally ended up tracing it to a build issue; the CMake build check for -funwind-tables was failing (because of some missing link libraries), so compiler-rt wasn't being built with that flag, which in turn led to all backtraces failing with an error like the following: ==21748==AddressSanitizer CHECK failed: …/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc:116 &q...

...t; >> There’s this bug: https://bugs.llvm.org/show_bug.cgi?id=38468 <https://bugs.llvm.org/show_bug.cgi?id=38468>. >> >> I’ve managed to track it down to a configuration issue. The thing is that in order for libunwind to be usable on ARM Linux, it should be built with the -funwind-tables flag. This flag is conditionally set here: https://github.com/llvm/llvm-project/blob/master/libunwind/CMakeLists.txt#L294 <https://github.com/llvm/llvm-project/blob/master/libunwind/CMakeLists.txt#L294>, if the compiler “supports” it. >> > > Are you sure that libunwind be...

...quot;need unwind table to unwind" is probably true in almost all cases. At least in all where ARMException and DwarfCFIException are concerned, which is the ones we're discussing about. I'm beginning to think that there is no reason at all to have an uwtable attribute, given that the -funwind-tables is propagated to the back-end AND if we emit the table for one function we should do it for all. I believe the intent is: > -fexceptions/-fno-exceptions controls whether we generate code that > copes with exceptions passing through it. > Right. Landing pads, cleanups, etc. We...

...vm-dev at lists.llvm.org> wrote: >> >> >> There’s this bug: https://bugs.llvm.org/show_bug.cgi?id=38468. >> >> I’ve managed to track it down to a configuration issue. The thing is that in order for libunwind to be usable on ARM Linux, it should be built with the -funwind-tables flag. This flag is conditionally set here: https://github.com/llvm/llvm-project/blob/master/libunwind/CMakeLists.txt#L294, if the compiler “supports” it. >> >> >> Are you sure that libunwind being built without -funwind-tables is the >> cause of the bug? >> &...

On Thu, Feb 13, 2014 at 5:52 PM, Renato Golin <renato.golin at linaro.org> wrote: > On 13 February 2014 13:47, Evgeniy Stepanov <eugenis at google.com> wrote: >> Hm, I see that -funwind-tables on arm-linux-androideabi target >> replaces this "cantunwind" with a proper unwind table. >> Hence http://llvm-reviews.chandlerc.com/D2762. > > If Android is using EHABI (I think it is), the default now is to > output full tables all the time, everywhere. This...

...vm-dev at lists.llvm.org> wrote: >> >> >> There’s this bug: https://bugs.llvm.org/show_bug.cgi?id=38468. >> >> I’ve managed to track it down to a configuration issue. The thing is that in order for libunwind to be usable on ARM Linux, it should be built with the -funwind-tables flag. This flag is conditionally set here: https://github.com/llvm/llvm-project/blob/master/libunwind/CMakeLists.txt#L294, if the compiler “supports” it. >> >> >> Are you sure that libunwind being built without -funwind-tables is the >> cause of the bug? >> &...

...ngth 71745 bytes (70 Kb) opened URL ================================================== downloaded 70 Kb * installing *source* package ?randomForest? ... ** libs gcc -std=gnu99 -I/usr/lib64/R/include -I/usr/local/include -fpic -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -c classTree.c -o classTree.o classTree.c: In function ?predictClassTree?: classTree.c:414: warning: ?cbestsplit? may be used uninitialized in this function gcc -std=gnu99 -I/usr/lib64/R/include -I/usr/local/include -fpic -fmessage-length=0 -O2 -Wall -D_FORT...

...ng, breaking >> debuggers/profilers/sanitizers. > > In that case, my argument stands again. > > >> As I understand, the right way to enable basic unwind through any >> function (without emitting landing pands etc, unless they are needed >> for something else) is -funwind-tables. I'm going to add that in the >> driver for all sanitizers then. > > -funwind-tables are not yet understood by ARM, but it is for Dwarf EH. > I plan on moving ARM to the same style as Dwarf, so you can assume it > is correct. Hm, I see that -funwind-tables on arm-linux...

...ontains 4 entries: 0x5d4 <main>: 0x1 [cantunwind] because the latter prevent any unwinding, breaking debuggers/profilers/sanitizers. As I understand, the right way to enable basic unwind through any function (without emitting landing pands etc, unless they are needed for something else) is -funwind-tables. I'm going to add that in the driver for all sanitizers then. On Tue, Feb 11, 2014 at 6:20 PM, Renato Golin <renato.golin at linaro.org> wrote: > On 11 February 2014 14:12, Rafael Espíndola <rafael.espindola at gmail.com> wrote: >> Why fails? I would read a "g...

On 12 May 2014 20:20, Logan Chien <tzuhsiang.chien at gmail.com> wrote: > There is a known issue in the code generated by LLVM. > As a workaround, I am adding "-funwind-tables" to compile the unit tests. I thought I had fixed all of them. Do you have a bug number? > BTW, the LLVM revision which I am using is r207501. > It seems that the recent master has come regression on unwind_04 and > unwind_05. I'm using 208522. I haven't seen errors...

...inline checking for stdlib.h... (cached) yes checking for GNU libc compatible malloc... yes configure: creating ./config.status config.status: creating src/Makevars ** libs g++ -I/usr/lib64/R/include -I/usr/local/include -fpic -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -c equalize.cpp -o equalize.o equalize.cpp: In function ?Matrix& computeEqualization(Matrix&)?: equalize.cpp:69:31: warning: comparison between signed and unsigned integer expressions gcc -std=gnu99 -I/usr/lib64/R/include -I/usr/local/include -fpic -...

...l solution for problem 4 below before we start. 4. Clang EH control There are a number of Clang/LLVM options to control exception handling: * -fno-excetpion (enable/disable EH on C++ mode, off in C mode) * -fcxx-exception (no idea, is it objC++ specific? does it control tables in any way?) * -funwind-tables (forces uwtable attribute?) * -arm-disable-ehabi (ARM specific bogus flag) Those options are not always completely exclusive, and they damage different parts of the compilation process (as seen recently on the list), so we need a clear consensus on what each option mean (or should mean), a...

...line with my reasoning above. > Clang, on the other hand, always generates them. I guess it'll have to figure out what > to do based on its impressions on what language is being used to produce similar results. You can make GCC emit unwind tables for C if you use the command line option -funwind-tables. This could be useful if you are compiling C code which is called by C++ code and which itself calls C++ code and you wish the C++ exception to propagate through the C code. > I believe that emitting the tables on anything that could potentially interact > with exceptional code makes...

...;igraph' package. Unfortunately, the installation is aborted by an error: --snip-- gcc -std=gnu99 -I/usr/lib64/R/include -DNDEBUG -I/usr/local/include -DUSING_R -I. -Ics -Iglpk -Iglpk/amd -Iglpk/colamd -I/usr/local/include -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -g -DNDEBUG -DPACKAGE_VERSION=\"0.6\" -DINTERNAL_ARPACK -DIGRAPH_THREAD_LOCAL=/**/ -fpic -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -g -c rinterface.c -o rinterface.o rinterface....

On 7 February 2014 00:19, Richard Smith <richard at metafoo.co.uk> wrote: > This (-fexceptions and -g imply -funwind-tables) seems like it's probably > the right thing for most targets. With SjLj exceptions, -fexceptions > probably doesn't need -funwind-tables. > Thanks, I think that's the general consensus, yes. Do we have such logic in Clang at the moment? My original point was that the...

...______________ * installing *source* package ?lme4? ... ** libs gcc -std=gnu99 -I/usr/lib64/R/include -I/usr/local/include -I"/usr/lib64/R/library/Matrix/include" -I"/usr/lib64/R/library/stats/include" -fpic -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -c init.c -o init.o gcc -std=gnu99 -I/usr/lib64/R/include -I/usr/local/include -I"/usr/lib64/R/library/Matrix/include" -I"/usr/lib64/R/library/stats/include" -fpic -fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind...

On 20 March 2014 02:09, Rafael Espíndola <rafael.espindola at gmail.com> wrote: > I think this is just 2. It uses .eh_frame for unwinding proper. The > only difference in .eh_frame is that there is a personality function > defined. If there is no debug information, it should still be possible to unwind the stack via the saved LR on the stack, no? If there is only line info, you

...oss different platforms. I can't decide that, but those decisions should stay in the front-end. To the back-end, function attributes should be able to control table emission (or maybe we need flags, I don't know). > That said, the option already exists for changing the default: > -funwind-tables. There shouldn't be another ARM specific flag. > So, can I assume that -f{no-}unwind-tables's syntax is to completely enable/disable the unwind tables and add/remove the ELF sections from the objects? If that's so, I can easily remove -arm-disable-ehabi and check on that flag...

On Fri, Mar 28, 2014 at 09:42:52AM +0100, Olaf Hering wrote: > On Thu, Mar 27, Richard W.M. Jones wrote: > > > I'm pleased to announce libguestfs 1.26, a library and set of tools > > This fails to link at least in sles11sp3, 1.25.37 was still ok: > > ... > [ 288s] virt_index_validate-index-validate.o: In function `main': > [ 288s]