HP UX Software Transition Kit (STK) manual PA64 Mode Linker Options, Linker-Defined Symbols

Run-time Differences Between SOM (PA32) and ELF (PA64 and Itanium)

IPF applications (32-bit and 64-bit) and PA-64 applications use a run-time dynamic loading model similar to other SVR4 systems. Following are two main areas where the IPF/PA-64 program startup differs from PA 32-bit mode:

Table 17 Main areas where the IPF/PA-64 program startup differs from PA 32-bit mode

Linker and Loader Functions	PA-32 Mode Behavior
+s and +bpath_list ordering	Ordering is significant.
Symbol searching in dependent	Depth-first search order.
libraries
Run time path environment variables	No run time environment variables
	by default. If +s is specified, then
	SHLIB_PATH is available.

IPF (32-bit and 64-bit) and PA-64 Mode

Behavior

Ordering is insignificant by default. Use +compat to enforce ordering.

Breadth-first search order. Use +compat to enforce depth first ordering.

LD_LIBRARY_PATH and SHLIB_PATH are enabled by default. Use +noenvvar or +compat to turn off run-time path environment variables.

+bpath_list and -Ldirectories	-Ldirectoriesrecorded as absolute	-Ldirectoriesare not recorded in
interaction	paths in executables.	executables. Add all directories specified in
		-Lto +b path_list.

PA64 Mode Linker Options

This section describes the PA64 mode linker options.

Table 18 PA64 mode linker options

Option	Action
-dynamic	Forces the linker to create a shared executable. The linker looks for shared libraries first and
	then archived libraries. This option is on by default when you compile in PA64 mode.
-noshared	Forces the linker to create a fully bound archive program.
-k filename	Allows you to control the mapping of input section in the object file to segments in the output
	file.

+[no]allowunsats Enables/disables forced loading of all the object files from archive libraries. The linker accepts but ignores this option in 32-bit mode. It creates an executable (a.out).

+compat	Hides all symbols from being exported.
+[no]forceload	Instructs the linker not to load the default mapfile. See the -koption.
+hideallsymbols	Instructs the dynamic loader not to look at the LD_LIBRARY_PATH and SHLIB_PATH
	environment variables at runtime.
+nodefaultmap	Instructs the dynamic loader not to look at the LD_LIBRARY_PATH and SHLIB_PATH
	environment variables at runtime.
+noenvvar	Instructs the linker to use SVR4 compatible linking and loading behaviors. Default for PA64
	mode.
+std	Instructs the linker to use SVR4 compatible linking and loading behaviors. Default for PA64
	mode.
+stripunwind	Instructs the linker not to output the unwind table.
+vtype type	Produces verbose output about selected link operations.

Linker-Defined Symbols

This section describes the symbol names that linker reserves in PA64 mode (ELF). If an application uses any of these symbols, linker displays an error message.

82 Linker Toolset Differences Between PA-RISC and Itanium-Based Systems