Debugging WebAssembly can be mystifying, which is due to a lack of understanding about the right debugging tools and processes. To deal with complex problems during development, knowledge about practical debugging tools and related techniques is essential.

One such essential tool is the browser's debugging utility. Chrome, Firefox, and other popular browsers come with powerful developer tools that offer capabilities to debug WebAssembly.

Let's take Chrome's DevTools as an example. It features a dedicated debugging panel that allows inspection of wasm files. Using it, you can set breakpoints in your C++ code, step through the code, watch variables, and inspect the call stack. Here's a simple snippet to illustrate this process:

1#include <iostream>
2using namespace std;
3int main() {
4  // Trying some math in our wasm module
5  int a = 5;
6  int b = 10;
7  int c = a + b;
8  cout << "The sum of " << a << " and " << b << " is " << c << endl;
9  return 0;
10}

This is a simple addition operation, and in Chrome's DevTools, you can debug this C++ code compiled to wasm by setting breakpoints, watching variables a, b, and c, and examining the code execution.

Yet, there's a catch. To facilitate debugging, you need to compile your C++ code to WebAssembly in debug mode to include debugging information. Regular production build stripped of debugging info would make this hard to achieve.

It's also worth mentioning that the debugging capabilities for WebAssembly are continually improving. For instance, the WASI (WebAssembly System Interface) is a move towards enabling support for more powerful debugging tools that can go beyond what browser developer tools provide.

In the end, familiarizing yourself with these tools is a crucial step in mastering WebAssembly development. It helps you understand better what happens under the hood and ultimately lets you create more robust and efficient web applications.

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#include <iostream>

using namespace std;

int main() {

  // Trying some math in our wasm module

  int a = 5;

  int b = 10;

  int c = a + b;

  cout << "The sum of " << a << " and " << b << " is " << c << endl;

  return 0;

}