Debugger stepping incorrect in async method: execution flow jumps to else block after return #122577
Description
Description
I have encountered an issue with the debugger stepping behavior in an async method. When the code successfully executes a return statement inside a try block (which is nested within an if block), the debugger step-over (F10) action visually jumps the instruction pointer into the else block of the outer if statement.
Despite the debugger highlighting the code inside the else block, the method actually returns the correct value (from the if block), indicating that the compiled code execution is likely correct, but the sequence points or debugger information generated is misleading.
This behavior is confusing as it suggests that the fallback logic in the else block is being executed when it is not.
Reproduction Steps
I have attached a minimal reproduction project.
- Open the attached solution.
- Navigate to the
ShortenAsyncmethod (inShortLinkService.cs). - Set a breakpoint on the line:
var resultUrl = await AddOrGetShortUrlFromDbAsync(dbContext, newLink);
- Start debugging.
- When the breakpoint is hit, Step Over (F10).
Code snippet for context:
if (urlShortenerProviderResult.Success)
{
// ... object initialization ...
try
{
var resultUrl = await AddOrGetShortUrlFromDbAsync(dbContext, newLink); // <--- Breakpoint here
return resultUrl; // <--- Step Over this
}
catch (Exception e)
{
// ... logging ...
return shortUrl;
}
}
else
{
// Debugger jumps HERE after the return above
_logger.LogError("Can't get a short url from the provider...");
return longUrl;
}Expected behavior
After stepping over return resultUrl;, the debugger should exit the method or move to the closing brace of the method context. It should not highlight any lines inside the else block.
Actual behavior
The debugger execution pointer jumps to the else block (e.g., to the logging statement or the return longUrl line), creating the false impression that the if (Success) check failed or that the flow fell through.
Regression?
No response
Known Workarounds
No response
Configuration
.NET 10.0.101 x64
Windows 11
x64
Console App
Other information
No response