<div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Apr 3, 2014 at 5:04 AM, Greg Fitzgerald <span dir="ltr"><<a href="mailto:garious@gmail.com" target="_blank">garious@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="">> we would still want to use compiler-rt test-suite in a standalone mode, to test fully built/installed toolchains,<br>
and even GCC.<br>
<br>
</div>Sounds good.<br>
<div class=""><br>
<br>
> Clang driver links the static xsan runtimes from a hardcoded<br>
> paths in Clang resource directory, and doesn't add flags like<br>
> "-lasan -L/path/to/clang/resource/dir". I find this behavior reasonable.<br>
<br>
</div>Can we change the flags to "-lasan -L/path/to/clang/resource/dir"? If<br>
we make that change,</blockquote><div><br></div><div>I don't think it's a good idea to let user hijack the driver and stuff in custom version of</div><div>ASan runtime instead the one installed/built with compiler :)</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> I can stop suggesting that the clang build should<br>
invoke the compiler-rt test suite directly. :-)<br></blockquote><div><br></div><div>I haven't yet fully understood your complaints. Note that if you build/configure compiler-rt</div><div>in a standalone mode, then "make check-compiler-rt" in that tree wouldn't rebuild runtimes,</div>
<div>and instead assume that they are provided by toolchain (that is, in standalone mode runtimes and</div><div>test suites are effectively independent). What do you mean by "invoking the test-suite directly"?</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class=""><br>
<br>
> Do you want to give it a try?<br>
<br>
</div>I'll take a crack it, sure.<br>
<br>
<br>
By the way, locally, I now have just over half the ASan test suite<br>
passing ARM-Linux via QEMU. It's been really convenient to build<br>
compiler-rt in standalone mode. The edit-compile-run cycle is much<br>
shorter this way. Thanks for your help in making this work!<br>
<span class="HOEnZb"><font color="#888888"><br>
-Greg<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
<br>
<br>
On Wed, Apr 2, 2014 at 7:56 AM, Alexey Samsonov <<a href="mailto:samsonov@google.com">samsonov@google.com</a>> wrote:<br>
> Hi Greg,<br>
><br>
> On Wed, Apr 2, 2014 at 2:50 AM, Greg Fitzgerald <<a href="mailto:garious@gmail.com">garious@gmail.com</a>> wrote:<br>
>><br>
>> Alexey, Evgeniy,<br>
>><br>
>> I propose the following steps to unify multi-arch support in compiler-rt:<br>
>><br>
>> 1) The compiler-rt test suite adds "-L${CMAKE_CURRENT_BINARY_DIR}/lib"<br>
>> to its 'clang' variables. This way we can test the sanitizers without<br>
>> installing any libs to the just-built-clang install directory.<br>
><br>
><br>
> This is possible, but please keep in mind that:<br>
> 1) we would still want to use compiler-rt test-suite in a standalone mode,<br>
> to test fully built/installed toolchains,<br>
> and even GCC.<br>
> 2) Adding -L... wouldn't work: Clang driver links the static xsan runtimes<br>
> from a hardcoded paths in Clang resource directory,<br>
> and doesn't add flags like "-lasan -L/path/to/clang/resource/dir". I find<br>
> this behavior reasonable.<br>
><br>
> I don't see a problem with the current approach - we can make "run sanitizer<br>
> test suite" command in the<br>
> top-level build tree depend on "build/install compiler-rt ExternalProject"<br>
> steps (see how it's done currently).<br>
><br>
>><br>
>><br>
>> 2) The "clang/runtime" build calls ExternalProject once for each arch<br>
>> it needs of compiler-rt. So once to create x86_64 libs and once for<br>
>> i386 libs.<br>
>><br>
>> 3) The compiler-rt build drops the ${arch} suffix from its libs, and<br>
>> the "clang/runtime" build uses CMAKE_INSTALL_PREFIX to control where<br>
>> the compiler-rt libs go.<br>
>><br>
>> "CMAKE_INSTALL_PREFIX=${CMAKE_CURRENT_BINARY_DIR}/lib/clang/${CLANG_VERSION}/x86_64-linux"<br>
>><br>
>><br>
>> 4) Remove multi-arch support from the compiler-rt build. Instead,<br>
>> declare compiler-rt as an "any-arch" build, configured with:<br>
>> CMAKE_CXX_COMPILER (defaults to just-built-clang)<br>
>> CMAKE_CXX_FLAGS (defaults to llvm's default target)<br>
>> COMPILER_RT_TEST_COMPILER (defaults to CMAKE_CXX_COMPILER)<br>
>> COMPILER_RT_TEST_FLAGS (defaults to CMAKE_CXX_FLAGS)<br>
><br>
><br>
> Unfortunately, this could be problematic for Mac - we use "universal<br>
> binaries" there - a single static/dynamic runtime<br>
> which contains runtimes for all the possible architectures. We might work<br>
> around this, however, by adding a custom<br>
> Mac-specific step that would merge all single-arch binaries into a<br>
> multi-arch one - I think this is fine as long as we<br>
> greatly simplify the rest of the ugly build system.<br>
><br>
> Do you want to give it a try?<br>
><br>
>><br>
>><br>
>> Thoughts?<br>
>><br>
>> Thanks,<br>
>> Greg<br>
>><br>
>> On Tue, Apr 1, 2014 at 12:58 AM, Evgeniy Stepanov<br>
>> <<a href="mailto:eugeni.stepanov@gmail.com">eugeni.stepanov@gmail.com</a>> wrote:<br>
>> > It does sound like Android is better suited for "honest"<br>
>> > cross-compilation, rather than "build compiler-rt for all targets we<br>
>> > can find" model.<br>
>> ><br>
>> > I'm still not convinced that we must require the "ninja install" step.<br>
>> > Could we just "ninja clang" and then build the second stage against<br>
>> > the first stage build directory? Will this "find_package" thing not<br>
>> > work that way, or do you mean it as a way to copy target asan runtime<br>
>> > where the first stage compiler will find it (or probably both)?<br>
>> ><br>
>> > On Mon, Mar 31, 2014 at 6:46 PM, Alexey Samsonov <<a href="mailto:samsonov@google.com">samsonov@google.com</a>><br>
>> > wrote:<br>
>> >><br>
>> >> On Fri, Mar 28, 2014 at 10:56 PM, Greg Fitzgerald <<a href="mailto:garious@gmail.com">garious@gmail.com</a>><br>
>> >> wrote:<br>
>> >>><br>
>> >>> > Note that ASan tests on Android require llvm-symbolizer binary.<br>
>> >>><br>
>> >>> That's a really good point. And I see that llvm-symbolizer can't just<br>
>> >>> be pulled into compiler-rt because it has dependencies on DebugInfo,<br>
>> >>> Object, and Support libraries.<br>
>> >>><br>
>> >>><br>
>> >>> This throws a big wrench in Alexey's plan to have the native<br>
>> >>> compiler-rt build generate the cross-compiled binaries for all<br>
>> >>> supported targets. We would need to do the same in the llvm repo.<br>
>> >>> The alternative is to run a separate cross-compiled build for each<br>
>> >>> architecture. :-/<br>
>> >><br>
>> >><br>
>> >> Yes, this llvm-symbolizer part is frustrating... I though we can get<br>
>> >> away<br>
>> >> with it at first, as llvm-symbolizer is optional, and we generally<br>
>> >> won't be<br>
>> >> able<br>
>> >> to produce working *binaries* for architectures different from the host<br>
>> >> one<br>
>> >> (we might not have a linker, for instance).<br>
>> >> Android with its NDK looks like an exception, though.<br>
>> >><br>
>> >>><br>
>> >>><br>
>> >>><br>
>> >>> > Yes, so "ninja install" is optional.<br>
>> >>><br>
>> >>> But the 'install' depends on the 'all' target.<br>
>> >>><br>
>> >>> -Greg<br>
>> >>><br>
>> >>><br>
>> >>><br>
>> >>><br>
>> >>><br>
>> >>><br>
>> >>> On Fri, Mar 28, 2014 at 12:39 AM, Evgeniy Stepanov<br>
>> >>> <<a href="mailto:eugeni.stepanov@gmail.com">eugeni.stepanov@gmail.com</a>> wrote:<br>
>> >>> > On Thu, Mar 27, 2014 at 10:18 PM, Greg Fitzgerald<br>
>> >>> > <<a href="mailto:garious@gmail.com">garious@gmail.com</a>><br>
>> >>> > wrote:<br>
>> >>> >>> Alexey's approach with CMake sub-projects.<br>
>> >>> >><br>
>> >>> >> I prefer that direction as well, but what I've proposed is a<br>
>> >>> >> solution<br>
>> >>> >> that works today. To support cross-compilation, we'll need to loop<br>
>> >>> >> over each supported arch (llvm-config --targets-built), then loop<br>
>> >>> >> over<br>
>> >>> >> each supported triple for each arch (hard-coded map?), and then<br>
>> >>> >> pair<br>
>> >>> >> up each triple with a sysroot (system paths provided by the user).<br>
>> >>> >><br>
>> >>> >><br>
>> >>> >>> I think it already copies<br>
>> >>> >>> compiler-rt build products to the parent build directory, right?<br>
>> >>> >><br>
>> >>> >> The Android compiler-rt build does this, but in an unnecessarily<br>
>> >>> >> complex way. My proposal is a simplification of that process.<br>
>> >>> >> What<br>
>> >>> >> is described in "llvm/cmake/platforms/Android.cmake" is to build<br>
>> >>> >> llvm+clang for the host architecture and then run a second build to<br>
>> >>> >> cross-compile llvm+compiler-rt to get a the ASan shared object and<br>
>> >>> >> test suite. Instead, I propose building only llvm for the host<br>
>> >>> >> architecture (for the purpose of building llvm-config) and then<br>
>> >>> >> only<br>
>> >>> >> compile compiler-rt for Android. No need to build clang or to<br>
>> >>> >> cross-compile llvm.<br>
>> >>> >><br>
>> >>> >><br>
>> >>> >>> Requiring that llvm is installed complicates things.<br>
>> >>> >><br>
>> >>> >> Sorry for the confusion. By "llvm install directory", I don't mean<br>
>> >>> >> to<br>
>> >>> >> install llvm to the root directory. I'm referring to the<br>
>> >>> >> intermediary<br>
>> >>> >> directory pointed to by CMAKE_INSTALL_PREFIX. When you run "ninja<br>
>> >>> >> install", the build populates this directory with only the libs,<br>
>> >>> >> headers, docs, and executables that the LLVM build intends<br>
>> >>> >> customers<br>
>> >>> >> to use directly. In the case of compiler-rt, we need LLVM's<br>
>> >>> >> "bin/llvm-config" to determine the build mode, flags, and targets<br>
>> >>> >> available.<br>
>> >>> ><br>
>> >>> > Yes, so "ninja install" is optional. This should work with LLVM<br>
>> >>> > build<br>
>> >>> > directory just as well.<br>
>> >>> ><br>
>> >>> >><br>
>> >>> >><br>
>> >>> >>> This should not be too hard to fix.<br>
>> >>> >><br>
>> >>> >> Porting the LLVM build to Android? That seems like a more<br>
>> >>> >> challenging<br>
>> >>> >> solution than to cut out the unused cross-compiled llvm build.<br>
>> >>> ><br>
>> >>> > Note that ASan tests on Android require llvm-symbolizer binary.<br>
>> >>> > Building just compiler-rt for the target would not be enough.<br>
>> >>> ><br>
>> >>> >><br>
>> >>> >> -Greg<br>
>> >>> >><br>
>> >>> >> On Thu, Mar 27, 2014 at 1:14 AM, Evgeniy Stepanov<br>
>> >>> >> <<a href="mailto:eugeni.stepanov@gmail.com">eugeni.stepanov@gmail.com</a>> wrote:<br>
>> >>> >>> I'd prefer something based on Alexey's approach with CMake<br>
>> >>> >>> sub-projects. I think it already copies compiler-rt build products<br>
>> >>> >>> to<br>
>> >>> >>> the parent build directory, right?<br>
>> >>> >>><br>
>> >>> >>> Requiring that llvm is installed complicates things.<br>
>> >>> >>><br>
>> >>> >>> On Thu, Mar 27, 2014 at 5:00 AM, Greg Fitzgerald<br>
>> >>> >>> <<a href="mailto:garious@gmail.com">garious@gmail.com</a>><br>
>> >>> >>> wrote:<br>
>> >>> >>>> The build for the Android sanitizers is unique in that it needs<br>
>> >>> >>>> to<br>
>> >>> >>>> link against the Android system libraries to create a shared<br>
>> >>> >>>> object<br>
>> >>> >>>> and its test suites. The current solution to build ASan is to<br>
>> >>> >>>> drop<br>
>> >>> >>>> the compiler-rt repo into the llvm source tree and cross-compile<br>
>> >>> >>>> the<br>
>> >>> >>>> llvm build for Android. This is a bit awkward for few reasons:<br>
>> >>> >>>><br>
>> >>> >>>> 1) Not all of llvm can be cross-compiled for Android. "ninja<br>
>> >>> >>>> all"<br>
>> >>> >>>> causes expected build errors.<br>
>> >>> >>><br>
>> >>> >>> This should not be too hard to fix.<br>
>> >>> >>><br>
>> >>> >>>> 2) The sanitizers don't depend on any LLVM libraries, only<br>
>> >>> >>>> llvm-config<br>
>> >>> >>>> for its build configuration.<br>
>> >>> >>>> 3) No "install" rule. Instead, you cherry-pick files from the<br>
>> >>> >>>> build<br>
>> >>> >>>> directory.<br>
>> >>> >>>><br>
>> >>> >>>> Building against the LLVM install directory cleans this up nicely<br>
>> >>> >>>> and<br>
>> >>> >>>> as it turns out, this mostly works today (see CMake configuration<br>
>> >>> >>>> below). The only missing pieces are that the shared object is<br>
>> >>> >>>> not<br>
>> >>> >>>> added to the install directory and the test suites are not built.<br>
>> >>> >>>> Is<br>
>> >>> >>>> this a build configuration you'd consider using?<br>
>> >>> >>>><br>
>> >>> >>>> $ cmake -G Ninja .. \<br>
>> >>> >>>> -DCMAKE_INSTALL_PREFIX=ship \<br>
>> >>> >>>> -DCMAKE_C_COMPILER=arm-linux-androideabi-gcc \<br>
>> >>> >>>> -DCMAKE_CXX_COMPILER=arm-linux-androideabi-g++ \<br>
>> >>> >>>> -DCMAKE_PREFIX_PATH=`pwd`/../../llvm/out/ship \<br>
>> >>> >>>> -DANDROID=1 \<br>
>> >>> >>>> -DCMAKE_SYSTEM_NAME=Linux \<br>
>> >>> >>>><br>
>> >>> >>>> -DCMAKE_C_FLAGS=--sysroot=$(ndkDir)/platforms/android-19/arch-arm<br>
>> >>> >>>> \<br>
>> >>> >>>><br>
>> >>> >>>><br>
>> >>> >>>> -DCMAKE_CXX_FLAGS=--sysroot=$(ndkDir)/platforms/android-19/arch-arm<br>
>> >>> >>>> ...<br>
>> >>> >>>> $ ninja install<br>
>> >>> >>>> ...<br>
>> >>> >>>> [68/68]<br>
>> >>> >>>> -- Install configuration: "Release"<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/asan_interface.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/common_interface_defs.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/dfsan_interface.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/linux_syscall_hooks.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/lsan_interface.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/msan_interface.h<br>
>> >>> >>>> -- Installing: ship/include/sanitizer/tsan_interface_atomic.h<br>
>> >>> >>>> -- Installing: ship/asan_blacklist.txt<br>
>> >>> >>>> -- Installing: ship/bin/asan_device_setup<br>
>> >>> >>>><br>
>> >>> >>>> Thanks,<br>
>> >>> >>>> Greg<br>
>> >><br>
>> >><br>
>> >><br>
>> >><br>
>> >> --<br>
>> >> Alexey Samsonov, MSK<br>
><br>
><br>
><br>
><br>
> --<br>
> Alexey Samsonov, MSK<br>
</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div>Alexey Samsonov, MSK</div>
</div></div>