Debugging with GDB (February 2008)
Table Of Contents
- Summary of GDB
- A Sample GDB Session
- Getting In and Out of GDB
- GDB Commands
- Running Programs Under GDB
- Stopping and Continuing
- Examining the Stack
- Examining Source Files
- Examining Data
- Using GDB with Different Languages
- Examining the Symbol Table
- Altering Execution
- GDB Files
- Specifying a Debugging Target
- HP-UX Configuration-Specific Information
- Summary of HP Enhancements to GDB
- HP-UX dependencies
- Supported Platforms and Modes
- HP-UX targets
- Support for Alternate root
- Specifying object file directories
- Fix and continue debugging
- Inline Support
- Debugging Macros
- Debugging Memory Problems
- When to suspect a memory leak
- Memory debugging restrictions
- Memory Debugging Methodologies
- Debugging Memory in Interactive Mode
- Debugging Memory in Batch Mode
- Debugging Memory Interactively After Attaching to a Running Process
- Configuring memory debugging settings
- Scenarios in memory debugging
- Stop when freeing unallocated or deallocated blocks
- Stop when freeing a block if bad writes occurred outside block boundary
- Stop when a specified block address is allocated or deallocated
- Scramble previous memory contents at malloc/free calls
- Detect dangling pointers and dangling blocks
- Detect in-block corruption of freed blocks
- Specify the amount of guard bytes for every block of allocated memory
- Comparison of Memory Debugging Commands in Interactive Mode and Batch Mode
- Heap Profiling
- Memory Checking Analysis for User Defined Memory Management Routines
- Commands to track the change in data segment value
- Thread Debugging Support
- Debugging MPI Programs
- Debugging multiple processes ( programs with fork and vfork calls)
- Debugging Core Files
- Printing the Execution Path Entries for the Current Frame or Thread
- Invoking GDB Before a Program Aborts
- Aborting a Command Line Call
- Instruction Level Stepping
- Enhanced support for watchpoints and breakpoints
- Debugging support for shared libraries
- Language support
- Enhanced Java Debugging Support
- Commands for Examining Java Virtual Machine(JVM) internals
- Support for stack traces in Java, C, and C++ programs
- Support for 64-bit Java, C, aC++ stack unwinding
- Enhanced support for C++ templates
- Support for __fpreg data type on IPF
- Support for _Complex variables in HP C
- Support for debugging namespaces
- Command for evaluating the address of an expression
- Viewing Wide Character Strings
- Support for output logging
- Getting information from a non-debug executable
- Debugging optimized code
- Visual Interface for WDB
- Starting and stopping Visual Interface for WDB
- Navigating the Visual Interface for WDB display
- Specifying foreground and background colors
- Using the X-window graphical interface
- Using the TUI mode
- Changing the size of the source or debugger pane
- Using commands to browse through source files
- Loading source files
- Editing source files
- Editing the command line and command-line history
- Saving the contents of a debugging session to a file
- Support for ddd
- Support for XDB commands
- GNU GDB Logging Commands
- Support for command line calls in a stripped executable
- Displaying the current block scope information
- Linux support
- The HP-UX Terminal User Interface
- XDB to WDB Transition Guide
- By-function lists of XDB commands and HP WDB equivalents
- Overall breakpoint commands
- XDB data formats and HP WDB equivalents
- XDB location syntax and HP WDB equivalents
- XDB special language operators and HP WDB equivalents
- XDB special variables and HP WDB equivalents
- XDB variable identifiers and HP WDB equivalents
- Alphabetical lists of XDB commands and HP WDB equivalents
- Controlling GDB
- Canned Sequences of Commands
- Using GDB under gnu Emacs
- GDB Annotations
- The gdb/mi Interface
- Function and purpose
- Notation and terminology
- gdb/mi Command Syntax
- gdb/mi compatibility with CLI
- gdb/mi output records
- gdb/mi command description format
- gdb/mi breakpoint table commands
- gdb/mi Data manipulation
- gdb/mi program control
- Miscellaneous GDB commands in gdb/mi
- gdb/mi Stack Manipulation Commands
- gdb/mi Symbol query commands
- gdb/mi Target Manipulation Commands
- gdb/mi thread commands
- gdb/mi tracepoint commands
- gdb/mi variable objects
- Reporting Bugs in GDB
- Installing GDB
- Index
Chapter 14: HP-UX Configuration-Specific Information 141
(This step is not required on Integrity systems.)
To explicitly preload the librtc runtime library and start the target application,
enter one of the following commands:
- For 32 bit IPF applications,
LD_PRELOAD=/opt/langtools/lib/hpux32/librtc.so <executable>
- For 64 bit IPF applications,
LD_PRELOAD=/opt/langtools/lib/hpux64/librtc.so <executable>
- For 32 bit PA applications,
LD_PRELOAD=/opt/langtools/lib/librtc.sl <executable>
- For 64-bit PA applications,
LD_PRELOAD=/opt/langtools/lib/pa20_64/librtc.sl <executable>
If LD_PRELOAD and chatr +mem_check are used to preload the librtc runtime
library , the librtc runtime library is loaded from the path specified by LD_
PRELOAD.
Note:
Batch Mode RTC displays one of the following errors and causes the pro-
gram to temporarily hang if the version of WDB and librtc.[sl|so] do
not match, or if WDB is not available on the system:
"/opt/langtools/bin/gdb: unrecognized option ‘-brtc’
Use ‘/opt/langtools/bin/gdb --help’ for a complete list of options."
(OR)
"execl failed. Cannot print RTC info: No such file or directory"
This error does not occur under normal usage where WDB or
librtc.[sl|so] is used from the default location at /opt/langtools/...
However, this error occurs if GDB_SERVER and/or LIBRTC_SERVER are set
to a mismatched version of WDB or librtc.[sl|so] respectively.
5. At the end of the run, output data file is created in output_data_dir, if defined in
rtcconfig,or the current directory. HP WDB creates output data file for each run. It
creates a separate file for leak detection and heap information. The naming convention
for output files is as follows:
<file_name>.<pid>.<suffix>
Where, <pid> is the process id and the value for <suffix> can be either leaks, heap, or
mem.
Note:
During operations such as system(3s)and popen(), which invoke a new
shell, librtc.sl|so must not be loaded to the invoked shell. You must
use LD_PRELOAD_ONCE, instead of LD_PRELOAD, to exclusively load the
librtc.sl|so file to the calling process only. Following is the syntax for
using LD_PRELOAD_ONCE:
LD_PRELOAD_ONCE= /opt/langtools/lib/librtc.sl