Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions

  




 

 

7.11. Java Exceptions

The Java language uses a slightly different exception handling model from C++. Normally, GNU C++ will automatically detect when you are writing C++ code that uses Java exceptions, and handle them appropriately. However, if C++ code only needs to execute destructors when Java exceptions are thrown through it, GCC will guess incorrectly. Sample problematic code is:

  struct S { ~S(); };
  extern void bar();    // is written in Java, and may throw exceptions
  void foo()
  {
    S s;
    bar();
  }

The usual effect of an incorrect guess is a link failure, complaining of a missing routine called __gxx_personality_v0.

You can inform the compiler that Java exceptions are to be used in a translation unit, irrespective of what it might think, by writing #pragma GCC java_exceptions at the head of the file. This #pragma must appear before any functions that throw or catch exceptions, or run destructors when exceptions are thrown through them.

You cannot mix Java and C++ exceptions in the same translation unit. It is believed to be safe to throw a C++ exception from one file through another file compiled for the Java exception model, or vice versa, but there may be bugs in this area.

 
 
  Published under the terms of the GNU General Public License Design by Interspire