HP-UX Linker and Libraries Release Notes (September, 2007 )

Link-time Checking Support for Unaligned Data Access Errors
The linker detects potential unaligned data access errors when resolving uninitialized data
symbols. An unaligned access error can occur when a data variable is defined with different
sizes in different object modules.
This feature is introduced on Integrity and PA64 systems. This feature is already supported on
PA32 systems.
New Linker Features for PA32 Systems
Following are the new features in this release of HP-UX Linker and Libraries that support PA32
systems:
New RTLD_VERBOSE Flag for the dlopen Routine
The dlopen routine supports a new RTLD_VERBOSE flag. This flag directs the dynamic loader
to display verbose messages when binding symbols.
RTLD_VERBOSE Modifier
If RTLD_VERBOSE is ORed with the flags parameter, the dynamic loader displays verbose
messages for all the unresolved symbols. You can use this option to view the symbols that are
not bound.
Typically, RTLD_VERBOSE is used with RTLD_NOW to debug unresolved symbols.
For example:
...
void *dl =dlopen("unsat.sl", RTLD_NOW | RTLD_VERBOSE);
...
Using _HP_DLDOPTS to Enable RTLD_VERBOSE, and BIND_VERBOSE
You can enable the RTLD_VERBOSE flag for dlopen, and the BIND_VERBOSE flag for shl_load
routine, by using the _HP_DLDOPTS environment variable instead of specifying the flags in the
dlopen and shl_load routines. The_HP_DLDOPTS environment variable enables
RTLD_VERBOSE, and BIND_VERBOSE for existing programs without changing the code.
To set the RTLD_VERBOSE and the BIND_VERBOSE flags by using _HP_DLDOPTS, enter the
following command at the HP-UX prompt:
$ export _HP_DLOPTS=-load_verbose
This flag is available only on PA32 systems.
chatr/dld Support for Memory Leak Checking
This feature is supported on Integrity systems, PA64 systems, and PA32 systems.
For more information, see “chatr/dld Support for Memory Leak Checking” (page 6)
Documentation Overview
This section addresses the following topics:
• “Before You Begin” (page 8)
• “Accessing HP-UX Linker Online Help” (page 9)
• “Related Information” (page 9)
Before You Begin
Before you begin to use the HP-UX Linker Online Help, complete the following steps:
8 HP-UX Linker and Libraries Release Notes (September 2007)