WasmFS: FS.readFile doesn't work with BigInt

[kd935]

Version of emscripten/emsdk:

emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.17-git (529028e5b243d7fb5ce0cb7ac7fbd67ea27cbb17)
clang version 15.0.0 (https://github.com/llvm/llvm-project 7c51f02effdbd0d5e12bfd26f9c3b2ab5687c93f)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: D:\emsdk\upstream\bin

Failing command line in full:

#include <stdio.h>
#include <emscripten/emscripten.h>

int main()
{
  EM_ASM({
    FS.writeFile("/read_file.txt", new Uint8Array([1, 2, 3]));
    console.log(FS.readFile("/read_file.txt")); // expected 123
  });
  return 0;
}

Full link command and output with -v appended:

D:\emscripten>em++ -v D:/build/test.cpp -o D:/build/test.html -s FORCE_FILESYSTEM=1 -s WASM_BIGINT=1 -sWASMFS=1
 "D:/emsdk/upstream/bin\clang++.exe" -target wasm32-unknown-emscripten -DEMSCRIPTEN -D__EMSCRIPTEN_major__=3 -D__EMSCRIPTEN_minor__=1 -D__EMSCRIPTEN_tiny__=17 -fignore-exceptions -fvisibility=default -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr -Werror=implicit-function-declaration -Xclang -iwithsysroot/include/SDL --sysroot=D:\emscripten\cache\sysroot -Xclang -iwithsysroot/include\compat -v D:/build/test.cpp -c -o C:\Users\kdots\AppData\Local\Temp\emscripten_temp_1dvjasn1\test_0.o
clang version 15.0.0 (https://github.com/llvm/llvm-project 7c51f02effdbd0d5e12bfd26f9c3b2ab5687c93f)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: D:\emsdk\upstream\bin
 (in-process)
 "D:\\emsdk\\upstream\\bin\\clang++.exe" -cc1 -triple wasm32-unknown-emscripten -emit-obj -mrelax-all --mrelax-relocations -disable-free -clear-ast-before-backend -main-file-name test.cpp -mrelocation-model static -mframe-pointer=none -ffp-contract=on -fno-rounding-math -mconstructor-aliases -target-cpu generic -mllvm -treat-scalable-fixed-error-as-warning -debugger-tuning=gdb -v "-fcoverage-compilation-dir=D:\\emscripten" -resource-dir "D:\\emsdk\\upstream\\lib\\clang\\15.0.0" -D EMSCRIPTEN -D __EMSCRIPTEN_major__=3 -D __EMSCRIPTEN_minor__=1 -D __EMSCRIPTEN_tiny__=17 -isysroot "D:\\emscripten\\cache\\sysroot" -internal-isystem "D:\\emscripten\\cache\\sysroot/include/wasm32-emscripten/c++/v1" -internal-isystem "D:\\emscripten\\cache\\sysroot/include/c++/v1" -internal-isystem "D:\\emsdk\\upstream\\lib\\clang\\15.0.0\\include" -internal-isystem "D:\\emscripten\\cache\\sysroot/include/wasm32-emscripten" -internal-isystem "D:\\emscripten\\cache\\sysroot/include" -Werror=implicit-function-declaration -fdeprecated-macro "-fdebug-compilation-dir=D:\\emscripten" -ferror-limit 19 -fmessage-length=166 -fvisibility default -fgnuc-version=4.2.1 -fcxx-exceptions -fignore-exceptions -fexceptions -fcolor-diagnostics -iwithsysroot/include/SDL "-iwithsysroot/include\\compat" -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr -o "C:\\Users\\kdots\\AppData\\Local\\Temp\\emscripten_temp_1dvjasn1\\test_0.o" -x c++ D:/build/test.cpp
clang -cc1 version 15.0.0 based upon LLVM 15.0.0git default target x86_64-pc-windows-msvc
ignoring nonexistent directory "D:\emscripten\cache\sysroot/include/wasm32-emscripten/c++/v1"
ignoring nonexistent directory "D:\emscripten\cache\sysroot/include/wasm32-emscripten"
#include "..." search starts here:
#include <...> search starts here:
 D:\emscripten\cache\sysroot/include/SDL
 D:\emscripten\cache\sysroot/include\compat
 D:\emscripten\cache\sysroot/include/c++/v1
 D:\emsdk\upstream\lib\clang\15.0.0\include
 D:\emscripten\cache\sysroot/include
End of search list.
 "D:/emsdk/upstream/bin\wasm-ld.exe" -o D:/build/test.wasm C:\Users\kdots\AppData\Local\Temp\emscripten_temp_1dvjasn1\test_0.o -LD:\emscripten\cache\sysroot\lib\wasm32-emscripten --whole-archive -lwasmfs-debug --no-whole-archive -lGL -lal -lhtml5 -lstubs-debug -lnoexit -lc-debug -ldlmalloc -lcompiler_rt -lc++-noexcept -lc++abi-noexcept -lsockets -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --import-undefined --strip-debug --export-if-defined=main --export-if-defined=__start_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__main_argc_argv --export-if-defined=fflush --export=emscripten_stack_get_end --export=emscripten_stack_get_free --export=emscripten_stack_get_base --export=emscripten_stack_init --export=_wasmfs_read_file --export=_wasmfs_write_file --export=_wasmfs_mkdir --export=_wasmfs_chdir --export=_wasmfs_symlink --export=_wasmfs_chmod --export=_wasmfs_identify --export=_wasmfs_readdir_start --export=_wasmfs_readdir_get --export=_wasmfs_readdir_finish --export=stackSave --export=stackRestore --export=stackAlloc --export=__wasm_call_ctors --export=__errno_location --export=malloc --export=free --export-table -z stack-size=5242880 --initial-memory=16777216 --no-entry --max-memory=16777216 --global-base=1024
 "D:/emsdk/node/14.18.2_64bit/bin/node.exe" D:\emscripten\src\compiler.js C:\Users\kdots\AppData\Local\Temp\tmp39dx14kp.json
 "D:/emsdk/upstream/bin\llvm-objcopy.exe" D:/build/test.wasm D:/build/test.wasm --remove-section=.debug* --remove-section=producers
 "D:/emsdk/node/14.18.2_64bit/bin/node.exe" D:\emscripten\tools\preprocessor.js C:\Users\kdots\AppData\Local\Temp\emscripten_temp_1dvjasn1\settings.js shell.html

Output with WasmFS:

test.js:2092 Uncaught TypeError: Cannot mix BigInt and other types, use explicit conversions
    at Object.readFile (test.js:2092:67)
    at 5524 (test.js:1147:91)
    at _emscripten_asm_const_int (test.js:1373:31)
    at main (test.cpp:6)
    at main (test.wasm:0x895)
    at test.js:959:22
    at callMain (test.js:2743:15)
    at doRun (test.js:2800:23)
    at test.js:2811:7

Expected output (when building without WasmFS):

123

[kleisauke]

See: #17316.