OpenCV.js --simd build fails with recent Emscripten #18097
Description
System information (version)
- OpenCV => recent master (949fe93)
- Operating System / Platform => OSX
- Compiler => Emscripten 2.0.0
Detailed description
Multiple source files fail with
In file included from .../opencv/modules/core/include/opencv2/core/hal/intrin.hpp:228:
.../opencv/modules/core/include/opencv2/core/hal/intrin_wasm.hpp:2810:55: error: use of undeclared identifier 'wasm_i8x16_mul'
Recent versions of Emscripten are based on LLVM 12. This version has an intrinsics headers that doesn't contain functions used by OpenCV that were present in e.g. LLVM 9 (e.g. in Emscripten 1.38.33).
~/Documents/emsdk/upstream/bin $ ./llc --version
LLVM (http://llvm.org/):
LLVM version 12.0.0git
Optimized build with assertions.
Default target: x86_64-apple-darwin19.4.0
Host CPU: skylake-avx512
Registered Targets:
wasm32 - WebAssembly 32-bit
wasm64 - WebAssembly 64-bit
x86 - 32-bit X86: Pentium-Pro and above
x86-64 - 64-bit X86: EM64T and AMD64
Steps to reproduce
# install Emscripten 2.0.0
cd emsdk/
emsdk install 2.0.0
emsdk activate 2.0.0
./emsdk_env.sh
# build OpenCV.js
cd opencv/platforms/js/
emmake python build_js.py build --simd