Bug 7935 - Compiler crashes compiling an implicit/explicit conversion operator with no parameters.
Summary: Compiler crashes compiling an implicit/explicit conversion operator with no p...
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2012-10-23 03:09 UTC by Ben Cooley
Modified: 2012-10-29 06:26 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Ben Cooley 2012-10-23 03:09:48 UTC
This code will cause the compiler to crash:

public class Test {

  public implicit operator string () {
      return null;

  // also explicit will cause the crash

This code will also cause monodevelop to crash as well when typing the method with no parameters.

Looking at the compiler code, it seems that the parser does not check whether the proper number of parameters are defined for operator overload methods before the semantic Resolve() method is called.  The Resolve() method then assumes there is at least one parameter and null ref exception occurs.
Comment 1 Marek Safar 2012-10-29 06:26:57 UTC
Fixed in master