Reference Guide

44 Chapter 3
HP-UX Architecture Conventions
Sections in 64-bit Mode
Sections in 64-bit Mode
In 64-bit mode, the Executable and Linking Format (ELF) uses segments
and sections rather than spaces and subspaces.
The concept of spaces maps to the ELF concept of segments, but
segments do not apply to relocatable object files. Hence, the Assembler
ignores the .SPACE directive for 64-bit assembly programs. Subspaces
map directly to the ELF concept of sections, so the .SUBSPA directive
switches to or creates a new section. The attributes of a subspace
correspond to section attributes as follows:
• Subspace names listed in the table are mapped to their corresponding
section name. Names not in this table are unchanged.
$GLOBAL$ 40 Global variable base address.
$PLT 6 Procedure linkage table.
$SHLIB_DATA$ 12 Shared library data.
$SHORTBSS$ 80 Uninitialized data and common.
$SHORTDATA$ 24 Global scalar variables.
$THREAD_SPECIFIC$ 16
$TBSS$ 40 Thread local storage
Space Subspace Sort Key Use
SUBSPACE NAME SECTION NAME
$BSS$ .bss
$CODE$ .text
$DATA$ .data
$FINI$ .fini