Ah... that was simply the optimizer resolving the math code into a constant expression. Reproduction test cases incoming :)
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. 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