Programming Forums - View Single Post - Code Segfaults when compiled with optimizations, doesn't in arbitrary situations

Jessehk · Feb 9th, 2008, 8:50 PM

I don't expect people to look through the complicated code that is the problem. I'm mostly looking for some debugging advice because I'm obviously doing something wrong, but at a loss of where to look.

When I compile my code with debugging on, there are no memory errors (checked with valgrind) and everything runs perfectly.

When I compile a "release" mode which includes -O3 and -DNDEBUG, the code segfaults almost immediately. However, when I insert a single output statement in one area of code,

ie,

 c++ Syntax (Toggle Plain Text) 
std::cout << "Fine" << std::endl;
std::cout << "Fine" << std::endl;

and recompile (with the same optimizations), everything runs perfectly once again.
Does anyone recognize any symptoms here or have any advice on what class of errors might be causing this bizarre behavior?

Thanks in advance.

Feb 9th, 2008, 8:50 PM	#1
Jessehk The Oblivious One Join Date: May 2005 Location: Ontario, Canada Posts: 641 Rep Power: 4	Code Segfaults when compiled with optimizations, doesn't in arbitrary situations I don't expect people to look through the complicated code that is the problem. I'm mostly looking for some debugging advice because I'm obviously doing something wrong, but at a loss of where to look. When I compile my code with debugging on, there are no memory errors (checked with valgrind) and everything runs perfectly. When I compile a "release" mode which includes -O3 and -DNDEBUG, the code segfaults almost immediately. However, when I insert a single output statement in one area of code, ie, c++ Syntax (Toggle Plain Text) std::cout << "Fine" << std::endl; std::cout << "Fine" << std::endl; and recompile (with the same optimizations), everything runs perfectly once again. Does anyone recognize any symptoms here or have any advice on what class of errors might be causing this bizarre behavior? Thanks in advance. __________________ Dr. Zoidberg: [ecstatic] I'm going to a movie... with FRIENDS!