WasmFS: Zero file size using fetch backend with WASM_BIGINT

[kd935]

Version of emscripten/emsdk:

emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.19-git (5c4b1675ca5ba34e283b21b3c01df092827db628)
clang version 16.0.0 (https://github.com/llvm/llvm-project 786b503f66b1a35f79312203fcb533ad27511982)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: D:\emsdk\upstream\bin

Failing command line in full:

#include <iostream>
#include <unistd.h>
#include <emscripten/wasmfs.h>

int main()
{
  // File contents - "hello from file.txt"
  const char *filePath = "file.txt";
  const char *url = "http://localhost:8000/file.txt";

  backend_t backend = wasmfs_create_fetch_backend(url);
  int fd = wasmfs_create_file(filePath, S_IRWXU | S_IRWXG | S_IRWXO, backend);

  struct stat stat_buf;
  int rc = fstat(fd, &stat_buf);
  int size = rc == 0 ? stat_buf.st_size : -1;

  printf("File size is - %d\n", size);
  return 0;
}

Full link command and output with -v appended:

D:\emscripten>em++ -v D:/build/test.cpp -o D:/build/test.html -s WASMFS=1 -s USE_PTHREADS=1 -sPTHREAD_POOL_SIZE=4 -sEXIT_RUNTIME=1 -sWASM_BIGINT=1
 "D:/emsdk/upstream/bin\clang++.exe" -target wasm32-unknown-emscripten -fignore-exceptions -fvisibility=default -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr -D__EMSCRIPTEN_SHARED_MEMORY__=1 -DEMSCRIPTEN -D__EMSCRIPTEN_major__=3 -D__EMSCRIPTEN_minor__=1 -D__EMSCRIPTEN_tiny__=19 -Werror=implicit-function-declaration -ID:\emscripten\cache\sysroot\include\SDL --sysroot=D:\emscripten\cache\sysroot -Xclang -iwithsysroot/include\compat -v -pthread D:/build/test.cpp -c -o C:\Users\kdots\AppData\Local\Temp\emscripten_temp_81yad4hj\test_0.o
clang version 16.0.0 (https://github.com/llvm/llvm-project 786b503f66b1a35f79312203fcb533ad27511982)
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-feature +atomics -target-feature +bulk-memory -target-feature +mutable-globals -target-feature +sign-ext -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\\16.0.0" -D __EMSCRIPTEN_SHARED_MEMORY__=1 -D EMSCRIPTEN -D __EMSCRIPTEN_major__=3 -D __EMSCRIPTEN_minor__=1 -D __EMSCRIPTEN_tiny__=19 -I "D:\\emscripten\\cache\\sysroot\\include\\SDL" -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\\16.0.0\\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=183 -fvisibility default -pthread -fgnuc-version=4.2.1 -fcxx-exceptions -fignore-exceptions -fexceptions -fcolor-diagnostics "-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_81yad4hj\\test_0.o" -x c++ D:/build/test.cpp
clang -cc1 version 16.0.0 based upon LLVM 16.0.0git 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\16.0.0\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_81yad4hj\test_0.o -LD:\emscripten\cache\sysroot\lib\wasm32-emscripten D:\emscripten\cache\sysroot\lib\wasm32-emscripten\crtbegin.o --whole-archive -lwasmfs-mt-debug --no-whole-archive -lGL-mt -lal -lhtml5 -lstubs-debug -lc-mt-debug -ldlmalloc-mt -lcompiler_rt-mt -lc++-mt-noexcept -lc++abi-mt-noexcept -lsockets-mt -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --import-undefined --import-memory --shared-memory --strip-debug --export-if-defined=main --export-if-defined=_emscripten_thread_init --export-if-defined=_emscripten_thread_exit --export-if-defined=_emscripten_thread_crashed --export-if-defined=_emscripten_tls_init --export-if-defined=pthread_self --export-if-defined=__start_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__start_em_js --export-if-defined=__stop_em_js --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=stackSave --export=stackRestore --export=stackAlloc --export=__wasm_call_ctors --export=__errno_location --export=emscripten_dispatch_to_thread_ --export=_emscripten_thread_free_data --export=emscripten_main_browser_thread_id --export=emscripten_main_thread_process_queued_calls --export=emscripten_run_in_main_runtime_thread_js --export=emscripten_stack_set_limits --export=emscripten_proxy_finish --export=__funcs_on_exit --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\tmpszdyuuo9.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_81yad4hj\settings.js worker.js --expandMacros
 "D:/emsdk/node/14.18.2_64bit/bin/node.exe" D:\emscripten\tools\preprocessor.js C:\Users\kdots\AppData\Local\Temp\emscripten_temp_81yad4hj\settings.js shell.html

Output with WASM_BIGINT:

File size is - 0

Expected output (without WASM_BIGINT):

File size is - 19