openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

[PATCH] kbuild: Set NOSTDINC_FLAGS late to speed up compile (a little) 

Move definition of NOSTDINC_FLAGS below inclusion of arch Makefile, so
any arch specific settings to $(CC) takes effect before looking up the
compiler include directory.

The previous solution that replaced ':=' with '=' caused gcc to be
invoked one additional time for each directory visited.

This decreases kernel compile time with 0.1 second (3.6 -> 3.5 seconds) when
running make on a fully built kernel

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Sam Ravnborg 2005-04-30 16:51:42 -07:00 committed by Linus Torvalds
parent b3d9ae4b98
commit e8e6993178
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
Makefile
View File

@ -332,9 +332,7 @@ KALLSYMS = scripts/kallsyms
PERL = perl
CHECK = sparse
NOSTDINC_FLAGS = -nostdinc -isystem $(shell $(CC) -print-file-name=include)
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__
CHECKFLAGS += $(NOSTDINC_FLAGS)
MODFLAGS = -DMODULE
CFLAGS_MODULE = $(MODFLAGS)
AFLAGS_MODULE = $(MODFLAGS)
@ -531,6 +529,10 @@ endif
include $(srctree)/arch/$(ARCH)/Makefile
# arch Makefile may override CC so keep this after arch Makefile is included
NOSTDINC_FLAGS := -nostdinc -isystem $(shell $(CC) -print-file-name=include)
CHECKFLAGS += $(NOSTDINC_FLAGS)
# warn about C99 declaration after statement
CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)