LC

Compile a C Function to Wasm and Inspect the Binary

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PrevParse a Wasm Binary Module: Sections, Types, Function Bodies

Language

Compiler

2.0s Limit 256MB

Implementation

Write a C program that documents the Wasm compilation workflow for a simple add function.

Requirements:

Print a header describing the compilation pipeline
Show the C source code for an exported add function
Show the clang and wasm-ld commands used
Show the resulting WAT output
Explain the magic bytes and version in the binary
Describe why attribute((visibility("default"))) is needed
Include the terms: Wasm, compile, binary, WAT

Why This Matters

This exact clang --target=wasm32 and wasm-ld pipeline (or its Emscripten wrapper) is how Figma and AutoCAD ported their existing C++ codebases to run at near-native speed inside a browser tab. The __attribute__((visibility("default"))) export step you're documenting is the real reason a compiled function is callable from JavaScript at all — without it, wasm-ld strips the symbol entirely.

Hints

0 / 3 revealed

Validation Suite

main.c

Workspace 1.0