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//
// Build with
//
// -pthread -s PROXY_TO_PTHREAD -s EXIT_RUNTIME
//

#include <stdlib.h>

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

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# 1 "tests/core/test_atomic_cxx.cpp"
# 1 "<built-in>" 1
# 1 "<built-in>" 3
# 355 "<built-in>" 3
# 1 "<command line>" 1
# 1 "<built-in>" 2
# 1 "tests/core/test_atomic_cxx.cpp" 2
# 13 "tests/core/test_atomic_cxx.cpp"
# 1 "/home/azakai/Dev/emscripten/cache/sysroot/include/c++/v1/atomic" 1 3
# 577 "/home/azakai/Dev/emscripten/cache/sysroot/include/c++/v1/atomic" 3

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*.wasm
temp

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Building binaryen with zig cc

1. Add zigcc, zigc++ scripts because cmake doens't accept a compiler with spaces in the name like "zig cc".
2. The zigcc/zigc++ scripts can also add a target for cross-compiling as shown here.
3. Disable threads (perhaps cmake cross-compiling needs to be set up?).
4. Use a static build (otherwise cmake emits a .so - again, do we need cmake cross-compiling here?).
5. ninja stalls on the final links: it just hangs. To solve that, run ninja wasm-opt and so forth manually, as a specific build target works.

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extern "C" int foo();

int main() {
  foo();
}

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  (func $ThreadMain\28void*\29 (param $0 i32) (result i32)
   (local $1 i32)
   (local $2 i32)
   (loop $label$1
    (local.set $0
     (call $__cxa_allocate_exception
      (i32.const 4)
     )
    )
    (block $label$2

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diff --git a/src/tools/wasm-emscripten-finalize.cpp b/src/tools/wasm-emscripten-finalize.cpp
index 221629557..8381b0bb6 100644
--- a/src/tools/wasm-emscripten-finalize.cpp
+++ b/src/tools/wasm-emscripten-finalize.cpp
@@ -49,21 +49,21 @@ int main(int argc, const char* argv[]) {
   std::string dataSegmentFile;
   bool emitBinary = true;
   bool debugInfo = false;
   bool DWARF = false;
   bool sideModule = false;

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(module
 (type $i32_=>_i32 (func (param i32) (result i32)))
 (type $i32_i32_i32_=>_i32 (func (param i32 i32 i32) (result i32)))
 (type $i32_=>_none (func (param i32)))
 (type $i32_i32_i32_=>_none (func (param i32 i32 i32)))
 (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
 (type $none_=>_i32 (func (result i32)))
 (type $i32_i32_i32_i32_=>_i32 (func (param i32 i32 i32 i32) (result i32)))
 (type $i32_f64_i32_i32_i32_i32_=>_i32 (func (param i32 f64 i32 i32 i32 i32) (result i32)))
 (type $i32_i32_=>_none (func (param i32 i32)))

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Simple WasmBoxC Library Example

This shows how to easily sandbox a real-world library using WasmBoxC. Specifically we sandbox the zlib compression library.

To follow along with this, you can clone this gist and then do the following commands.

First, get the emsdk:

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Sizes

(html+js+wasm)

Non-emscripten: 19,964 bytes
Emscripten:     11,086 bytes