On Fri, Nov 12, 2021 at 4:10 AM Floh <[email protected]> wrote: > Ah... that was simply the optimizer resolving the math code into a > constant expression. Reproduction test cases incoming :) >
Yes, all these LTO issues related to LLVM creating references to symbols during LTO that didn't exist prior. There has been an upstream LLVM issue open for a while now: https://bugs.llvm.org/show_bug.cgi?id=44353 Hopefully this change is enough to address them: https://github.com/emscripten-core/emscripten/pull/15497 cheers, sam > On Friday, 12 November 2021 at 13:02:26 UTC+1 Floh wrote: > >> I started a github issue here: >> https://github.com/emscripten-core/emscripten/issues/15506 >> >> ...unfortunately I haven't been able to create a simple reproducer yet, >> building a simple test program which calls into one of the exp, exp2 or pow >> functions appears to work, with or without lto. >> >> On Friday, 12 November 2021 at 12:23:09 UTC+1 Floh wrote: >> >>> > I suspect LTO is the culprit here. >>> >>> That's indeed the issue. Building without LTO works. I'll try to come up >>> with a minimal reproducer, create a github ticket and then see if I can get >>> your PR working with my local emsdk installation :) >>> >>> On Thursday, 11 November 2021 at 23:08:14 UTC+1 [email protected] wrote: >>> >>>> I think this should fix your issue: >>>> https://github.com/emscripten-core/emscripten/pull/15497 >>>> >>>> On Thu, Nov 11, 2021 at 1:44 PM Sam Clegg <[email protected]> wrote: >>>> >>>>> >>>>> >>>>> On Thu, Nov 11, 2021 at 4:46 AM Floh <[email protected]> wrote: >>>>> >>>>>> These are the related header/source pairs in MUSL, and it seems that >>>>>> these are new (didn't exist in the stable SDK): >>>>>> >>>>>> >>>>>> https://github.com/emscripten-core/emscripten/blob/main/system/lib/libc/musl/src/math/exp_data.h >>>>>> >>>>>> https://github.com/emscripten-core/emscripten/blob/main/system/lib/libc/musl/src/math/exp_data.c >>>>>> >>>>>> >>>>>> https://github.com/emscripten-core/emscripten/blob/main/system/lib/libc/musl/src/math/exp2f_data.h >>>>>> >>>>>> https://github.com/emscripten-core/emscripten/blob/main/system/lib/libc/musl/src/math/exp2f_data.c >>>>>> >>>>>> When listing the libc.a symbols in the emscripten cache with llvm-nm >>>>>> I can see the entry for exp_data but nothing for exp2f_data: >>>>>> >>>>>> exp_data.o: >>>>>> -------- D __exp_data >>>>>> >>>>>> (which is doubly weird, why does exp_data produce a linker error even >>>>>> though it's there, and why isn't exp2f_data anywhere to be found) >>>>>> >>>>>> ...anyway, that's how far I got :) >>>>>> >>>>> >>>>> I suspect LTO is the culprit here. Does you non-LTO build work? >>>>> >>>>> I think these symbols can get generated at codegen time which can >>>>> confuse LTO because it likes to know all the symbols needed before running >>>>> the compiler/LTO. >>>>> >>>>> >>>>> >>>>>> On Thursday, 11 November 2021 at 12:57:06 UTC+1 Floh wrote: >>>>>> >>>>>>> PS: my other WASM projects appear to work fine (the home computer >>>>>>> emulators here: https://floooh.github.io/tiny8bit/, and the Z80 and >>>>>>> 6502 netlist simulations: https://floooh.github.io/visualz80remix/, >>>>>>> https://floooh.github.io/visual6502remix/). >>>>>>> >>>>>>> On Thursday, 11 November 2021 at 12:02:12 UTC+1 Floh wrote: >>>>>>> >>>>>>>> I'm getting the following linker errors in my sokol-samples project: >>>>>>>> >>>>>>>> 5x: >>>>>>>> wasm-ld: error: >>>>>>>> /...cache/sysroot/lib/wasm32-emscripten/lto/libc.a(exp2f_data.o): >>>>>>>> undefined >>>>>>>> symbol: __exp2f_data >>>>>>>> >>>>>>>> 8x: >>>>>>>> wasm-ld: error: >>>>>>>> /...cache/sysroot/lib/wasm32-emscripten/lto/libc.a(exp_data.o): >>>>>>>> undefined >>>>>>>> symbol: __exp_data >>>>>>>> >>>>>>>> Full wasm-ld command line: >>>>>>>> >>>>>>>> em++: error: >>>>>>>> '/Users/floh/projects/fips-sdks/emsdk/upstream/bin/wasm-ld -o >>>>>>>> /Users/floh/projects/fips-deploy/sokol-samples/sapp-webgl2-wasm-ninja-release/modplay-sapp.wasm >>>>>>>> sapp/CMakeFiles/modplay-sapp.dir/modplay-sapp.c.obj >>>>>>>> libs/sokol/libsokol.a >>>>>>>> fips-libmodplug_libmodplug/liblibmodplug.a >>>>>>>> -L/Users/floh/projects/fips-sdks/emsdk/upstream/emscripten/cache/sysroot/lib/wasm32-emscripten/lto >>>>>>>> -lGL-webgl2 -lal -lhtml5 -lstubs -lc -lcompiler_rt -lc++-noexcept >>>>>>>> -lc++abi-noexcept -lemmalloc -lc_rt_wasm -lsockets -mllvm >>>>>>>> -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj >>>>>>>> -mllvm >>>>>>>> -disable-lsr --import-undefined --strip-debug --export-if-defined=main >>>>>>>> --export-if-defined=stackSave --export-if-defined=stackRestore >>>>>>>> --export-if-defined=stackAlloc --export-if-defined=__wasm_call_ctors >>>>>>>> --export-if-defined=__errno_location --export-if-defined=malloc >>>>>>>> --export-if-defined=free --export-if-defined=__start_em_asm >>>>>>>> --export-if-defined=__stop_em_asm --export-table -z stack-size=5242880 >>>>>>>> --initial-memory=33554432 --no-entry --max-memory=2147483648 >>>>>>>> <(214)%20748-3648> --global-base=1024' failed (returned 1) >>>>>>>> >>>>>>>> ...and the em++ command line: >>>>>>>> >>>>>>>> /Users/floh/projects/fips-sdks/emsdk/upstream/emscripten/em++ -s >>>>>>>> DISABLE_EXCEPTION_CATCHING=1 -fno-exceptions -fno-rtti -std=c++11 >>>>>>>> -fstrict-aliasing -Wall -Wno-multichar -Wextra -Wno-unknown-pragmas >>>>>>>> -Wno-ignored-qualifiers -Wno-long-long -Wno-overloaded-virtual >>>>>>>> -Wno-deprecated-writable-strings -Wno-unused-volatile-lvalue >>>>>>>> -Wno-inconsistent-missing-override -Wno-warn-absolute-paths >>>>>>>> -Wno-expansion-to-defined -flto -O3 -DNDEBUG -s >>>>>>>> DISABLE_EXCEPTION_CATCHING=1 --memory-init-file 0 -s >>>>>>>> INITIAL_MEMORY=33554432 -s ERROR_ON_UNDEFINED_SYMBOLS=1 -s >>>>>>>> NO_EXIT_RUNTIME=1 -s ALLOW_MEMORY_GROWTH=1 -s USE_WEBGL2=1 -s >>>>>>>> "MALLOC='emmalloc'" -s NO_FILESYSTEM=1 -s WASM=1 --shell-file >>>>>>>> /Users/floh/projects/sokol-samples/webpage/shell.html -O3 -flto >>>>>>>> --closure >>>>>>>> 1 -s ASSERTIONS=0 sapp/CMakeFiles/modplay-sapp.dir/modplay-sapp.c.obj >>>>>>>> -o >>>>>>>> /Users/floh/projects/fips-deploy/sokol-samples/sapp-webgl2-wasm-ninja-release/modplay-sapp.html >>>>>>>> libs/sokol/libsokol.a fips-libmodplug_libmodplug/liblibmodplug.a >>>>>>>> >>>>>>>> Investigating now, I think the most likely culprit is libmodplug (a >>>>>>>> MOD player library). >>>>>>>> >>>>>>>> Should I open a separate github ticket, or append this type of >>>>>>>> feedback to the PR? >>>>>>>> >>>>>>>> Cheers, >>>>>>>> -Andre. >>>>>>>> >>>>>>>> On Wednesday, 10 November 2021 at 17:33:34 UTC+1 [email protected] >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Yesterday I landed the update to musl v1.2.2: >>>>>>>>> https://github.com/emscripten-core/emscripten/pull/13006 >>>>>>>>> >>>>>>>>> This is a fairly large change so we decided that next emscripten >>>>>>>>> release will bump the version 3.0.0. >>>>>>>>> >>>>>>>>> If you are interested in helping us test this new version >>>>>>>>> before we release it it would be great if you could try installing the >>>>>>>>> `tot` version of emsdk which now contains this new version musl >>>>>>>>> (`./emsdk >>>>>>>>> install tot`). We are keen to find and fix any issues that might >>>>>>>>> arise from this change. >>>>>>>>> >>>>>>>>> cheers, >>>>>>>>> sam >>>>>>>>> >>>>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "emscripten-discuss" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/emscripten-discuss/ff0f0683-9ed5-44b0-b0be-f51267863559n%40googlegroups.com >>>>>> <https://groups.google.com/d/msgid/emscripten-discuss/ff0f0683-9ed5-44b0-b0be-f51267863559n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>> -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/emscripten-discuss/dc1badc0-77ea-4f08-85ba-40298631c025n%40googlegroups.com > <https://groups.google.com/d/msgid/emscripten-discuss/dc1badc0-77ea-4f08-85ba-40298631c025n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. 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