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# Debugging WebAssembly
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The following steps describe a common way to debug a WebAssembly module in
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Wasmtime:
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1. Compile your WebAssembly with debug info enabled, usually `-g`; for
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example:
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```sh
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clang foo.c -g -o foo.wasm
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```
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2. Run Wasmtime with the debug info enabled; this is `-g` from the CLI and
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`Config::debug_info(true)` in an embedding (e.g. see [debugging in a Rust
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embedding](./examples-rust-debugging.md))
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3. Use a supported debugger:
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```sh
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lldb -- wasmtime run -g foo.wasm
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```
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```sh
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gdb --args wasmtime run -g foo.wasm
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```
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If you run into trouble, the following discussions might help:
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- On MacOS with LLDB you may need to run: `settings set
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plugin.jit-loader.gdb.enable on`
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([#1953](https://github.com/bytecodealliance/wasmtime/issues/1953))
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- With LLDB, call `__vmctx.set()` to set the current context before calling any
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dereference operators
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([#1482](https://github.com/bytecodealliance/wasmtime/issues/1482)):
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```sh
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(lldb) p __vmctx->set()
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(lldb) p *foo
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```
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- The address of the start of instance memory can be found in `__vmctx->memory`
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