PPPS: building with "-sEXPORTED_FUNCTIONS=_calloc" also works, but I don't understand why I need this only for this one specific sample, for a problem triggered by a library that doesn't even call calloc. I didn't have to deal with EXPORTED_FUNCTIONS for years (instead EMSCRIPTEN_KEEPALIVE did the job), and especially never for any C runtime functions.
Any ideas of what's the issue here would be greatly appreciated. I'll put the EXPORTED_FUNCTIONS into my build options as a hack for now, but it would be nice if that wouldn't be needed (especially since I don't understand the reason, lol). Cheers! On Saturday, 3 September 2022 at 16:26:07 UTC+2 Floh wrote: > Another information tidbit: > > Adding a calloc() call in any of the other (very similar) samples always > works without problems (e.g. I don't need to add calloc to > EXPORTED_FUNCTIONS as advised by the emsdk linker - I don't use > EXPORTED_FUNCTIONS anywhere in my compiler settings). > > It also works if I remove any calls to that spine-c library in my own code > (but mind that the spine-c library doesn't call into calloc - emsdk's > llvm-nm doesn't show any references to calloc in the resulting library). > > The only place where I can find a reference to calloc is as 'weak symbol' > in libemmalloc.a, but I don't understand how any potential problems in > emmalloc would be triggered by the presence or absence of a random third > party library that doesn't even call into calloc... > > On Saturday, 3 September 2022 at 15:54:37 UTC+2 Floh wrote: > >> Ok, it works if I change one thing: setting the -O flag from -O3 to -O0 >> (-O1 also already breaks). >> >> ...also it seems that calloc *is* actually called somewhere (the wasm >> crashes in the calloc stub when I build with ERROR_ON_UNDEFINED_SYMBOLS=0). >> But I still think it's not anywhere in my code (e.g. the Spine runtime has >> CALLOC macros all over the place, but this resolves to a call to a helper >> function with malloc+memset. >> >> >> On Saturday, 3 September 2022 at 15:21:18 UTC+2 Floh wrote: >> >>> PPS: ...looks like I can only go back to SDK version 3.0.0 on ARM Macs, >>> and the problem already existed in that version. >>> >>> On Saturday, 3 September 2022 at 15:16:42 UTC+2 Floh wrote: >>> >>>> PS: this is the wasm-ld cmdline: >>>> >>>> em++: error: '/Users/floh/projects/fips-sdks/emsdk/upstream/bin/wasm-ld >>>> -o >>>> /Users/floh/projects/fips-deploy/sokol-samples/sapp-webgl2-wasm-vscode-release/spine-sapp.wasm >>>> >>>> sapp/CMakeFiles/spine-sapp.dir/spine-sapp.c.obj >>>> sapp/CMakeFiles/spine-sapp.dir/spine-assets.c.obj libs/sokol/libsokol.a >>>> libs/spine-c/libspine-c.a libs/stb/libstb.a libs/util/libfileutil.a >>>> fips-cimgui_cimgui/libcimgui.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 -lsockets -mllvm >>>> -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj >>>> -mllvm >>>> -disable-lsr >>>> --allow-undefined-file=/var/folders/dz/g9ydwg8973z9nn5bvffcwf3h0000gn/T/tmphqvycm26.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 >>>> --entry=main >>>> --max-memory=2147483648 --global-base=1024' failed (returned 1) >>>> >>>> ...I'm now trying to bisect the SDK version to see if this is a >>>> regression... >>>> >>>> On Saturday, 3 September 2022 at 15:03:21 UTC+2 Floh wrote: >>>> >>>>> I just stumbled over a very weird problem in a new sample for my sokol >>>>> headers which includes a non-trivial 3rd party C library - the spine-c >>>>> runtime ( >>>>> https://github.com/EsotericSoftware/spine-runtimes/tree/4.1/spine-c/spine-c >>>>> ) >>>>> >>>>> When building in release mode (but not in debug mode) the linker >>>>> complains about an unresolved 'calloc' call. Adding detailed output >>>>> via LLD_REPORT_UNDEFINED=1 I get tons of: >>>>> >>>>> wasm-ld: error: >>>>> /Users/floh/projects/fips-sdks/emsdk/upstream/emscripten/cache/sysroot/lib/wasm32-emscripten/lto/libemmalloc.a(emmalloc.o): >>>>> >>>>> undefined symbol: calloc >>>>> >>>>> ... how does that even make sense when emmalloc is supposed to provide >>>>> an implementation of calloc... anyway... >>>>> >>>>> The error goes away when compiling in debug mode (some differences >>>>> that come to mind to the release mode is that debug mode doesn't use >>>>> -flto, >>>>> and also doesn't run the closure compiler). >>>>> >>>>> The problem also goes away when not building with emmalloc. >>>>> >>>>> Now the weird thing is that the entire code this sample is built from >>>>> doesn't appear to call calloc anywhere... and that other samples which >>>>> actually use calloc build just fines. >>>>> >>>>> Has anybody seen a similar problem yet, before I jump myself into the >>>>> rabbit hole? :) >>>>> >>>>> The problematic command line is: >>>>> >>>>> em++ -s DISABLE_EXCEPTION_CATCHING=1 -fno-exceptions -fno-rtti >>>>> -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 LLD_REPORT_UNDEFINED=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/spine-sapp.dir/spine-sapp.c.obj >>>>> sapp/CMakeFiles/spine-sapp.dir/spine-assets.c.obj -o >>>>> /Users/floh/projects/fips-deploy/sokol-samples/sapp-webgl2-wasm-vscode-release/spine-sapp.html >>>>> >>>>> libs/sokol/libsokol.a libs/spine-c/libspine-c.a libs/stb/libstb.a >>>>> libs/util/libfileutil.a fips-cimgui_cimgui/libcimgui.a >>>>> >>>> -- 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/0cdd4547-e68f-477d-859a-ff728345aef9n%40googlegroups.com.
