emsdk

[AIwzx]

when i build it ,error occured
~/code/ncnn/ncnn-webassembly-nanodet-master/build$ cmake -DCMAKE_TOOLCHAIN_FILE=$EMSDK/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DWASM_FEATURE=basic ..
CMake Error at /home/inpg/code/ncnn/emsdk/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake:131 (message):
Failed to fetch compiler version information with command
"'/home/inpg/code/ncnn/emsdk/upstream/emscripten/emcc' -v"! Process
returned with error code 1.
Call Stack (most recent call first):
/usr/local/share/cmake-3.23/Modules/CMakeDetermineSystem.cmake:124 (include)
CMakeLists.txt:1 (project)

how can i solve it, please