HP-UX 11i December 2003 Release Notes

Programming
Miscellaneous
Chapter 15
293
• Support for ldd32, which lists dynamic dependencies of executable files or shared
libraries in dld.sl.
• Plabel cache, caches PLABELS at run-time, supported in ld and dld.sl.
• ld +dependdb and +dependdb_outputdir options generate dependency database,
ldb file.
• ld +objdebugonly (in both 32-bit and 64-bit) ignores debug information from non-
objdebug objects or archives and then proceeds in +objdebug mode.
• Special support for OGL's TLS shared library in dld (both 32- and 64-bit).
Tools Enhancements
• elfdump +ild displays incremental linking information.
• ar -x option allows modules from lib to keep datestamp.
•odump -tlssym option displays the TLS (thread) symbols.
• chatr +q3p enable/disable and q4p enable/disable option supports marking
3rd/4th quadrant for private data space.
• odump -verifyall option suppresses stub warnings on executable.
• odump -filtertable to displays the filtered shared library's implementation
libraries.
Details of Linker Changes
Incremental linking: Incremental linking provides significant linktime improvements
for compile-link-debug development cycles by processing only those input files that are
actually modified between cycles. Files that are not modified do not need to be
reprocessed. For large application, incremental linking may provide up to 10x (and
sometimes greater) improvements in linktime.
Unix 98: Support for the APIs dlopen, dlsym, dlerror and dlclose has been added for
32-bit programs.
Filtered Libraries: Filtered shared libraries divide up a large library into one filter
and several implementation libraries. The user links against the filter library, but the
real definitions of data and functions actually resides in the implementation libraries. At
run time, only those implementation libraries that are actually used are loaded. Filtered
libraries can be nested; an implementation library can itself be a filtered library
containing other implementation libraries.
GProf 32-bit support: GProf, an enhanced version of prof, produces call graph profile
data (along with the data generated by prof). While the profiling of shared libraries was
not supported in earlier releases, this release will now support profiling of shared
libraries using the environmental variable LD_PROFILE. No recompilation is required for
profiling shared libraries.
PLabel cache: +plabel_cache is added to 32-bit linker and dld.sl to control the
global symbol hash mechanism.
Compatibility
Various serious and critical defects were repaired.