Understanding Application binary interface (ABI)
- by Tim
I am trying to understand the concept of Application binary interface (ABI).
From The Linux Kernel Primer:
An ABI is a set of conventions that allows a linker to combine
separately compiled modules into one unit without recompilation, such
as calling conventions, machine interface, and operating-system
interface. Among other things, an ABI defines the binary interface
between these units. ... The benefits of conforming to an ABI are that
it allows linking object files compiled by different compilers.
From Wikipedia:
an application binary interface (ABI) describes the low-level
interface between an application (or any type of) program and the
operating system or another application.
ABIs cover details such as data type, size, and alignment; the calling
convention, which controls how functions' arguments are passed and
return values retrieved; the system call numbers and how an
application should make system calls to the operating system; and in
the case of a complete operating system ABI, the binary format of
object files, program libraries and so on.
I was wondering whether ABI depends on both the instruction set and
the OS. Are the two all that ABI depends on?
What kinds of role does ABI play in different stages of compilation:
preprocessing, conversion of code from C to Assembly, conversion of
code from Assembly to Machine code, and linking?
From the first quote above, it seems to me that ABI is needed for
only linking stage, not the other stages. Is it correct?
When is ABI needed to be considered?
Is ABI needed to be considered during programming in C,
Assembly or other languages? If yes, how are ABI and API different?
Or is it only for linker or compiler?
Is ABI specified for/in machine code, Assembly language,
and/or of C?
