arch.7: Clarify architecture-specific macro use

Compilers may define multiple variants of architecture-specific macros
(for example, both __x86_64 and __x86_64__).  Add a note that the macros
documented in arch.7 are the preferred ones for FreeBSD.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Ed Maste 2018-07-23 19:39:20 +00:00
parent da8e85391f
commit f84d8f0ce5

View File

@ -26,7 +26,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd February 5, 2018
.Dd July 23, 2018
.Dt ARCH 7
.Os
.Sh NAME
@ -342,6 +342,10 @@ Architecture-specific macros:
.It riscv64sf Ta Dv __riscv, Dv __riscv_xlen == 64
.It sparc64 Ta Dv __sparc64__
.El
.Pp
Compilers may define additional variants of architecture-specific macros.
The macros above are preferred for use in
.Fx .
.Ss Important Xr make 1 variables
Most of the externally settable variables are defined in the
.Xr build 7