[U-Boot] [U-Boot, 1/2] common: Add CCACHE variable to allow use of ccache

[Marek Vasut <marex@denx.de>]

Dear York Sun,

> On 05/20/2013 10:25 AM, Marek Vasut wrote:
> > Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache.
> > In case the user wants to use ccache, exporting CCACHE=ccache will do
> > the trick. It is of course possible to either make the cross-compiler
> > name into a shellscript which invokes the ccache and the compiler, but
> > setting this variable makes use of ccache easier and more convenient.
> > 
> > Using ccache becomes convenient when using MAKEALL for large build
> > tests, where the speedup after building the cache for the first time
> > is about 4-6 times.
> > 
> > Signed-off-by: Marek Vasut <marex@denx.de>
> > Cc: Tom Rini <trini@ti.com>
> > 
> > ---
> > config.mk |    8 +++++---
> > 
> >  1 file changed, 5 insertions(+), 3 deletions(-)
> > 
> > diff --git a/config.mk b/config.mk
> > index 1fd109f..d59ded2 100644
> > --- a/config.mk
> > +++ b/config.mk
> > @@ -98,6 +98,8 @@ else
> > 
> >  HOSTCC		= gcc
> >  endif
> > 
> > +HOSTCC		:= $(CCACHE) $(HOSTCC)
> > +
> > 
> >  ifeq ($(HOSTOS),cygwin)
> >  HOSTCFLAGS	+= -ansi
> >  endif
> > 
> > @@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL)
> > $(SRCTREE)/tools/binutils-version.sh $(AS))
> > 
> >  #
> >  # Include the make variables (CC, etc...)
> >  #
> > 
> > -AS	= $(CROSS_COMPILE)as
> > +AS	= $(CCACHE) $(CROSS_COMPILE)as
> > 
> >  # Always use GNU ld
> >  LD	= $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
> >  
> >  		then echo "$(CROSS_COMPILE)ld.bfd"; else echo 
"$(CROSS_COMPILE)ld";
> >  		fi;)
> > 
> > -CC	= $(CROSS_COMPILE)gcc
> > +CC	= $(CCACHE) $(CROSS_COMPILE)gcc
> > 
> >  CPP	= $(CC) -E
> >  AR	= $(CROSS_COMPILE)ar
> >  NM	= $(CROSS_COMPILE)nm
> > 
> > @@ -320,7 +322,7 @@ endif
> > 
> >  ########################################################################
> >  #
> > 
> > -export	HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE 
\
> > +export	HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
> > CCACHE \
> > 
> >  	AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
> >  
> >  export	CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS 
CPPFLAGS
> >  CFLAGS AFLAGS
> 
> Where did this patch go? I found it useful.

It needs additional fixes, try running with MAKEALL and you will see the problem 
-- the problem is you would need separate ccache for each MAKEALL thread.

Best regards,
Marek Vasut