Compiling Programs

The first step in getting a program ready for debugging is to add your compiler’s –g debugging command-line option. This option tells your compiler to generate symbol table debugging information; for example:

cc –g –o executable source_program

You can also debug programs that you did not compile using the –g option, or programs for which you do not have source code. For more information, see “Viewing the Assembler Version of Your Code”.

The following table presents some general considerations. “Compilers and Platforms in the TotalView Reference Guide contains additional considerations.

 

Compiler Option or Library	What It Does	When to Use It
Debugging symbols option (usually –g)	Generates debugging information in the symbol table.	Before debugging any program with TotalView.
Optimization option (usually –O)	Rearranges code to optimize your program’s execution. Some compilers won’t let you use the –O option and the –g option at the same time. Even if your compiler lets you use the –O option, don’t use it when debugging your program, since strange results often occur.	After you finish debugging your program.
multi-process programming library (usually dbfork)	Uses special versions of the fork() and execve() system calls. In some cases, you need to use the –lpthread option. For more information about dbfork, see “Linking with the dbfork Library” contained in the “Compilers and Platforms” Chapter of the TotalView Reference Guide.	Before debugging a multi-process program that explicitly calls fork() or execve(). See “Debugging Processes That Call the fork() Function” and “Debugging Processes that Call the execve() Function”.