.section

Defines a section of an object file.

  .section name [ ,alignment ] [ ,type ] [ ,flags ]

Parameters

name

Name of the section.

alignment

Alignment boundary.

type

Numeric value for the ELF section type, per the following table. The default type value is 1: (SHT_PROGBITS).

Table 1. ELF Section Header Types (SHT)
Type	Name	Meaning
0	NULL	Section header is inactive.
1	PROGBITS	Section contains information that the program defines.
2	SYMTAB	Section contains a symbol table.
3	STRTAB	Section contains a string table.
4	RELA	Section contains relocation entries with explicit addends.
5	HASH	Section contains a symbol hash table.
6	DYNAMIC	Section contains information used for dynamic linking.
7	NOTE	Section contains information that marks the file, often for compatibility purposes between programs.
8	NOBITS	Section occupies no space in the object file.
9	REL	Section contains relocation entries without explicit addends.
10	SHLIB	Section has unspecified semantics, so does not conform to the Application Binary Interface (ABI) standard.
11	DYNSYM	Section contains a minimal set of symbols for dynamic linking.

flags

Numeric value for the ELF section flags, per the the following table. The default flags value is 0x00000002, 0x00000001: (SHF_ALLOC+SHF_WRITE).

Table 2. ELF Section Header Flags (SHF)
Flag	Name	Meaning
0x00000001	WRITE	Section contains data that is writable during execution.
0x00000002	ALLOC	Section occupies memory during execution.
0x00000004	EXECINSTR	Section contains executable machine instructions.
0xF0000000	MASKPROC	Bits this mask specifies are reserved for processor-specific purposes.

Remarks

You can use this directive to create arbitrary relocatable sections, including sections to be loaded at an absolute address.

Most assemblers generate ELF (Executable and Linkable Format) object files, but a few assemblers generate COFF (Common Object File Format) object files.

The assembler supports this alternative syntax, which you may find convenient:

  .section   name,typestring

(The name parameter has the same role as in the full syntax. The typestring value can be text, data, rodata, bss, sdata, or so forth.)

Normally, repeating a .text directive would resume the previous .text section. But to have each .text directive create a separate section, include in this relocatable section the statement .option no_section_resume_on.

Example

This example specifies a section named vector, with an alignment of 4 bytes, and default type and flag values:

  .section vector,4