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Version of emscripten/emsdk:
emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 4.0.6 (1ddaae4d2d6dfbb678ecc193bc988820d1fc4633)
clang version 21.0.0git (https:/github.com/llvm/llvm-project 4775e6d9099467df9363e1a3cd5950cc3d2fde05)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: C:\Users\user\Downloads\emsdk\upstream\bin
Failing command line in full:
> emcc main.cpp -lembind
main.cpp:12:5: error: no matching function for call to 'function'
12 | function<int(int, int)>("add5", std::bind(&add, 5, std::placeholders::_1));
| ^~~~~~~~~~~~~~~~~~~~~~~
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include\emscripten/bind.h:666:6: note: candidate template ignored: substitution failure [with ReturnType = int (int, int)]: function
cannot return function type 'int (int, int)'
666 | void function(const char* name, ReturnType (*fn)(Args...), Policies...) {
| ^ ~~~~~~~~~~
1 error generated.
emcc: error: 'C:/Users/user/Downloads/emsdk/upstream/bin\clang.exe -target wasm32-unknown-emscripten -fignore-exceptions -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot -DEMSCRIPTEN -Xclang -iwithsysroot/include\fakesdl -Xclang -iwithsysroot/include\compat -c main.cpp -o C:\Users\user\AppData\Local\Temp\emscripten_temp_z_8dp2sz\main_0.o' failed (returned 1)
Full link command and output with -v appended:
> emcc main.cpp -lembind -v
"C:/Users/user/Downloads/emsdk/upstream/bin\clang.exe" -target wasm32-unknown-emscripten -fignore-exceptions -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot -DEMSCRIPTEN -Xclang -iwithsysroot/include\fakesdl -Xclang -iwithsysroot/include\compat -v -c main.cpp -o C:\Users\user\AppData\Local\Temp\emscripten_temp_qso33ae2\main_0.o
clang version 21.0.0git (https:/github.com/llvm/llvm-project 4775e6d9099467df9363e1a3cd5950cc3d2fde05)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: C:\Users\user\Downloads\emsdk\upstream\bin
(in-process)
"C:\\Users\\user\\Downloads\\emsdk\\upstream\\bin\\clang.exe" -cc1 -triple wasm32-unknown-emscripten -emit-obj -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name main.cpp -mrelocation-model static -mframe-pointer=none -ffp-contract=on -fno-rounding-math -mconstructor-aliases -target-cpu generic -fvisibility=hidden -debugger-tuning=gdb "-fdebug-compilation-dir=C:\\Users\\user\\Desktop\\Projects\\other\\embind-std-bind-repro" -v "-fcoverage-compilation-dir=C:\\Users\\user\\Desktop\\Projects\\other\\embind-std-bind-repro" -resource-dir "C:\\Users\\user\\Downloads\\emsdk\\upstream\\lib\\clang\\21" -D EMSCRIPTEN -isysroot "C:\\Users\\user\\Downloads\\emsdk\\upstream\\emscripten\\cache\\sysroot" -internal-isystem "C:\\Users\\user\\Downloads\\emsdk\\upstream\\emscripten\\cache\\sysroot/include/wasm32-emscripten/c++/v1" -internal-isystem "C:\\Users\\user\\Downloads\\emsdk\\upstream\\emscripten\\cache\\sysroot/include/c++/v1" -internal-isystem "C:\\Users\\user\\Downloads\\emsdk\\upstream\\lib\\clang\\21\\include" -internal-isystem "C:\\Users\\user\\Downloads\\emsdk\\upstream\\emscripten\\cache\\sysroot/include/wasm32-emscripten" -internal-isystem "C:\\Users\\user\\Downloads\\emsdk\\upstream\\emscripten\\cache\\sysroot/include" -fdeprecated-macro -ferror-limit 19 -fmessage-length=200 -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcxx-exceptions -fignore-exceptions -fexceptions -fcolor-diagnostics "-iwithsysroot/include\\fakesdl" "-iwithsysroot/include\\compat" -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr -o "C:\\Users\\user\\AppData\\Local\\Temp\\emscripten_temp_qso33ae2\\main_0.o" -x c++ main.cpp
clang -cc1 version 21.0.0git based upon LLVM 21.0.0git default target x86_64-pc-windows-msvc
ignoring nonexistent directory "C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include/wasm32-emscripten/c++/v1"
ignoring nonexistent directory "C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include/wasm32-emscripten"
#include "..." search starts here:
#include <...> search starts here:
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include\fakesdl
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include\compat
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include/c++/v1
C:\Users\user\Downloads\emsdk\upstream\lib\clang\21\include
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include
End of search list.
main.cpp:12:5: error: no matching function for call to 'function'
12 | function("add1", std::bind(&add, 1, std::placeholders::_1)); // error: no matching function for call to 'function'
| ^~~~~~~~
C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot/include\emscripten/bind.h:666:6: note: candidate template ignored: could not match 'ReturnType (*)(Args...)' against
'__bind<int (*)(int, int), int, const __ph<1> &>'
666 | void function(const char* name, ReturnType (*fn)(Args...), Policies...) {
| ^
1 error generated.
emcc: error: 'C:/Users/user/Downloads/emsdk/upstream/bin\clang.exe -target wasm32-unknown-emscripten -fignore-exceptions -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=C:\Users\user\Downloads\emsdk\upstream\emscripten\cache\sysroot -DEMSCRIPTEN -Xclang -iwithsysroot/include\fakesdl -Xclang -iwithsysroot/include\compat -v -c main.cpp -o C:\Users\user\AppData\Local\Temp\emscripten_temp_qso33ae2\main_0.o' failed (returned 1)
#include <emscripten/bind.h>
#include <functional>
using namespace emscripten;
int add(int a, int b) {
return a + b;
}
EMSCRIPTEN_BINDINGS(Example) {
function("add", &add);
function("add1", std::bind(&add, 1, std::placeholders::_1)); // error: no matching function for call to 'function'
}This is propbably not intended to be used that way, but I've tried many other approaches and it seems like std::bind isn't supported. The question is: is there any way to use std::bind with Embind?