Linking

Question 1

.text

Answer 1

The machine code of the compiled program, stores function defs.

Question 2

.rodata

Answer 2

Read only data, eg string constants in formatting strings, jump tables

Question 3

.data

Answer 3

INITIALIZED global and static C variables

Question 4

.bss

Answer 4

UN-INITIALIZED global and static C variables, values are allocated at runtime (“better save space”) that can be inited to zero (not pointers or structs)

Question 5

.symtab

Answer 5

symbol table, info about functions and global vars.

Question 6

.rel.text

Answer 6

A list of locations in the .text section that will need to be modified by the linker.

Question 7

.rel.data

Answer 7

relocation information for any global variables, that will need to be modified by the linker.

Question 8

.line

Answer 8

a mapping between source code and asm

Question 9

.strtab

Answer 9

string table for the symbol table in the .symtable and .debug.

Question 10

.debug

Answer 10

symbol table use to recover information about local vars and types defs for debugging purposes.

Question 11

Global Symbols

Answer 11

Symbols that can be referenced by other modules. non-static C functions and Global Vars.

Question 12

External Symbols

Answer 12

Global variables that are defined by “another” module

Question 13

Local Symbols

Answer 13

Functions and Globals var declared with STATIC. cannot be seem by other modules.

Question 14

COMMON

Answer 14

stores info about UN-INITIALIZED global vars

Question 15

Strong Symbol

Answer 15

function, or inited global var

Question 16

Weak Symbol

Answer 16

global Symbol that is un-initialized

Question 17

Resolve multiple strong symbols

Answer 17

Error. this cannot be done

Question 18

resolve multiple weak symbols

Answer 18

choose one arbitrarily

Question 19

resolve weak and strong symbol

Answer 19

choose the strong symbol

Question 20

Relocation Sections and Symbol definitions

Answer 20

1st step relocation. Linker merges all sections of the same type into a new aggregate section of the same type. then, run time memory addresses are assigned, each instr and global var has a unique address

Question 21

Relocating Symbol references within sections

Answer 21

linker modifies symbols in the code and data sections so that then now point to the correct runtime address