]> err.no Git - linux-2.6/commit
[PATCH] enable unit-at-a-time optimisations for gcc4
authorIngo Molnar <mingo@elte.hu>
Sat, 14 Jan 2006 21:21:29 +0000 (13:21 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Sun, 15 Jan 2006 02:27:15 +0000 (18:27 -0800)
commit9ab34fe76114b9538bfcaf3a9d112dee0feb5f17
tree3bd494625e6bef27f876d37f39fe537d554af571
parent40fc55cb69c0386504ab5184e9bea0a7aecb2bd3
[PATCH] enable unit-at-a-time optimisations for gcc4

Allow gcc4 compilers to optimize unit-at-a-time.

This flag enables gcc to "see" the entire C file before making optimisation
decisions such as inline, which results in gcc making better decisions.  One
of the immediate effects of this is that static functions that are used only
once now get inlined.

gcc 3.4 has this flag as well, however gcc 3.x have a problem with inlining
and stacks and as a result, enabling this flag there would cause excessive and
unacceptable stack use.  This problem is fixed in the gcc 4.x series.  The
x86-64 architecture already enables this feature so it's well tested already.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
arch/i386/Makefile