[question]How to use CMake with Emscripten and Conan 2

[Astral-Yang]

I've seen an example of emscripten in conan1, but it doesn't seem to be in conan2, what can I do to compile wasm in conan2?

[memsharded]

this would be a duplicate of #3829

[Astral-Yang]

this would be a duplicate of #3829

but i have some error, when i run
conan install . --profile:host=emscripten.profile --profile:build=default --build=missing
got

wasm-ld: error: blocksort.c.obj: section too large
emcc: error: '/usr/local/Cellar/emscripten/3.1.70/libexec/llvm/bin/wasm-ld -o bzip2.wasm -L/usr/local/Cellar/emscripten/3.1.70/libexec/cache/sysroot/lib/wasm32-emscripten CMakeFiles/bzip2.dir/src/bzip2.c.obj libbz2.a -lGL-getprocaddr -lal -lhtml5 -lstubs-debug -lnoexit -lc-debug -ldlmalloc -lcompiler_rt -lc++-noexcept -lc++abi-debug-noexcept -lsockets -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr /var/folders/q5/66ml___x5631tmxr9d5bhpcw0000gn/T/tmp2l82pu1wlibemscripten_js_symbols.so --export=emscripten_stack_get_end --export=emscripten_stack_get_free --export=emscripten_stack_get_base --export=emscripten_stack_get_current --export=emscripten_stack_init --export=_emscripten_stack_alloc --export=__get_temp_ret --export=__set_temp_ret --export=__wasm_call_ctors --export=_emscripten_stack_restore --export-if-defined=__start_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__start_em_lib_deps --export-if-defined=__stop_em_lib_deps --export-if-defined=__start_em_js --export-if-defined=__stop_em_js --export-if-defined=main --export-if-defined=__main_argc_argv --export-if-defined=fflush --export-table -z stack-size=65536 --no-growable-memory --initial-heap=16777216 --no-entry --stack-first --table-base=1' failed (returned 1)
make[2]: *** [bzip2] Error 1
make[1]: *** [CMakeFiles/bzip2.dir/all] Error 2
make: *** [all] Error 2
bzip2/1.0.8: ERROR:
Package '1c6dc9642a08a8abcc6d2dfdb73ea8d1443da9c7' build failed
bzip2/1.0.8: WARN: Build folder /Users/astralyang/.conan2/p/b/bzip23e0455484a97c/b/build/Debug
ERROR: bzip2/1.0.8: Error in build() method, line 64
cmake.build()
ConanException: Error 2 while executing

this emscripten.profile

[settings] arch=wasm build_type=Release compiler=apple-clang compiler.cppstd=gnu17 compiler.version=14 compiler.libcxx=libc++ os=Emscripten [platform_tool_requires] cmake/3.28.1 [buildenv] CC=emcc CXX=em++

this default
[settings] arch=x86_64 build_type=Release compiler=apple-clang compiler.cppstd=gnu17 compiler.libcxx=libc++ compiler.version=14 os=Macos

please help me,thank you

[memsharded]

I am afraid that this is not enough information. You'd need to provide:

• the conanfile that you are using. Ideally a minimal one to reproduce, do not provide one with tons of [requires], the best would be only 1
• It would be better to reproduce things with template projects, for example created with conan new cmake_lib command. Recipes, packages and third party libraries out there might not support wasm in their build systems at all, so this might not be a Conan issue, but an issue of those specific projects. So to report against Conan tool, it is better with a minimalistic project
• Report all the system details, including conan version command, your compiler details, etc
• Report the full output

Regarding point 2, the output in wasm-ld: error: blocksort.c.obj: section too large seems to indicate this is a compilation error, not a Conan error. Maybe that project cannot be compiled with wasm at all.

[Astral-Yang]

I am afraid that this is not enough information. You'd need to provide:

• the that you are using. Ideally a minimal one to reproduce, do not provide one with tons of , the best would be only 1conanfile``[requires]
• It would be better to reproduce things with template projects, for example created with command. Recipes, packages and third party libraries out there might not support wasm in their build systems at all, so this might not be a Conan issue, but an issue of those specific projects. So to report against Conan tool, it is better with a minimalistic projectconan new cmake_lib
• Report all the system details, including command, your compiler details, etcconan version
• Report the full output

Regarding point 2, the output in seems to indicate this is a compilation error, not a Conan error. Maybe that project cannot be compiled with wasm at all.wasm-ld: error: blocksort.c.obj: section too large

thank you for your reply，i fix it,but i do not know how to disable TensorflowLite's pthread in conan because i got an error when i compile

pthre7a01f8928a0fa/b/src/src/memory.c:44:7: error: call to undeclared function 'posix_memalign'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]

[memsharded]

This also looks like a compilation error, and pthread might not build at all for wasm.
In tensorflow-lite recipe the code is:

if Version(self.version) >= "2.12.0" or self.options.with_xnnpack:
     self.requires("pthreadpool/cci.20231129")

So for versions >=2.12 it seems the requirement to pthreadpool is mandatory, it cannot be skipped

[Astral-Yang]

这看起来也像一个编译错误，pthread 可能根本不为 wasm 构建。在 tensorflow-lite 配方中，代码为：

if Version(self.version) >= "2.12.0" or self.options.with_xnnpack:
     self.requires("pthreadpool/cci.20231129")

因此，对于版本 >=2.12，似乎要求是强制性的，不能跳过pthreadpool

Thanks for your help, could you give me a minimal example of compiling wasm? like conan1.x example