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C/C++

Built-in C/C++ WebAssembly plugin, shipped with wasmrun.

About​

The c plugin compiles C and C++ projects to WebAssembly using Emscripten. It is built-in: it ships inside the wasmrun binary, needs no separate installation, and its version tracks wasmrun itself.

Install​

Nothing to install for the plugin itself; it is always available.

Requirements:

# Verify Emscripten is available
emcc --version

Usage​

wasmrun auto-detects C/C++ projects from entry files (main.c, src/main.c, app.c, index.c) or a build file (Makefile, CMakeLists.txt):

# Compile and serve with the dev server
wasmrun ./my-c-project --watch

# Compile only
wasmrun compile ./my-c-project

# Plugin info
wasmrun plugin info c

If the project has a Makefile (also makefile or GNUmakefile), the plugin builds through it; otherwise it invokes emcc directly on the detected entry file.

What It Covers​

  • C and C++ sources: .c, .h, .cpp, .hpp, .cc, .cxx
  • Makefile builds: existing build setups are used as-is when present
  • Direct emcc compilation with .wasm + .js glue output
  • Web application output: Emscripten's web target alongside plain wasm
  • Optimization levels and live reload through wasmrun's dev server

What It Doesn't Cover​

  • Installing Emscripten: the SDK must be set up separately; wasmrun reports a clear error when emcc is missing
  • CMake builds: CMakeLists.txt is used for project detection, but compilation goes through Make or direct emcc, not a CMake pipeline
  • Running WASM: execution is handled by wasmrun (Server, Exec, or OS mode)

See Also​