Emscripten: Compile Settings Not Working Windows

[yahsaves]

I've been compiling a single C++ function into wasm for a while now on a windows environment. The function lives in a c++ file named "project.cpp" and the functions name is "project".

Below are my command line arguments:

emcc project.cpp -s WASM=1 -s EXPORTED_FUNCTIONS="['_project']" -s EXTRA_EXPORTED_RUNTIME_METHODS='["ccall", "cwrap"]' -o ../index.js

For several weeks this has been working great. However I just updated to the latest version of emscripten (don't remember which version I was using before) and now I get this error:

Error:root:cwrap]': No such file or directory ("cwrap]'" was expected to be an input file based on the command arguments provided).

In response I tried to compile it by seperating the "ccall" and "cwrap" mehtods into their own command like arguments:

-s EXTRA_EXPORTED_RUNTIME_METHODS='["cwrap"]' -s EXTRA_EXPORTED_RUNTIME_METHODS='["ccall"]'

And that just made my screen light up with errors.

So I tried to only do:

-s EXTRA_EXPORTED_RUNTIME_METHODS='["ccall"]'

That worked, as in it successfully built from the command line, however when I load the program in the browser I get this error:

Module.ccall is not a function

Has the latest update changed things? I can't not find anything in the documentation.

Edit ---------------------------------------------------------------

I just tried compiling the same c++ file on Linux using the same command line parameters I mentioned above and it worked. I am using 1.37.27 on Linux which to my understanding is the latest version (though I fear updating to verify that because I don't want to break my linux like I broke my windows).

Any help would be greatly appreciated!

[kripken]

This seems like a quoting issue, which was recently given some docs on the FAQ,

https://kripken.github.io/emscripten-site/docs/getting_started/FAQ.html#why-do-i-get-a-nameerror-or-a-problem-occurred-in-evaluating-content-after-a-s-when-i-use-a-s-option

However, it's very strange this worked before but fails later, since we didn't change anything there - this would have been always the case, assuming the OS and shell are the same. So maybe this is something other than quoting? But I would try the suggestion in that new faq entry, to quote like this:

-s "EXTRA_EXPORTED_RUNTIME_METHODS=['ccall', 'cwrap']"

[darkedges]

Following the example steps for compiling and using WASM (https://developer.mozilla.org/en-US/docs/WebAssembly/C_to_wasm) on Windows 10 (VS15/Python2.7 via npm install windows-build-tools) I found that I have to call the compiler like this to get it to work.

emcc -o hello.html hello.c -O3 -s WASM=1 --shell-file shell_minimal.html -s NO_EXIT_RUNTIME=1  -s "EXTRA_EXPORTED_RUNTIME_METHODS=['ccall']"

version details

emcc -v
emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 1.37.36
clang version 5.0.0 (https://github.com/kripken/emscripten-fastcomp-clang.git c8606950a97dea79eb578599bb13a48a1639661a) (https://github.com/kripken/emscripten-fastcomp.git 0d8129bb20f502b9ba26d54414f05120f5622b4b) (emscripten 1.37.36 : 1.37.36)
Target: x86_64-pc-windows-msvc
Thread model: posix
InstalledDir: C:\development\c\emsdk\clang\fastcomp\build_incoming_vs2015_64\Release\bin

[tskarthikus]

It works! Thanks.

[stale[bot]]

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