Re: [PATCH] fix include paths when the kernel source and build directory are different

[Jan Kiszka <jan.kiszka@siemens.com>]

Avi Kivity wrote:
> James Pike wrote:
>> Use correct architecture includes when kernel source and build directory
>> are different.
>> Signed-off-by: James Pike <james@chilon.net>
>>   --- a/Makefile
>> +++ b/Makefile
>> @@ -27,8 +27,9 @@ all:: prerequisite
>>  #    include header priority 1) $LINUX 2) $KERNELDIR 3) include-compat
>>      $(MAKE) -C $(KERNELDIR) M=`pwd` \
>>          LINUXINCLUDE="-I`pwd`/include -Iinclude \
>> -        $(if $(KERNELSOURCEDIR),-Iinclude2
>> -I$(KERNELSOURCEDIR)/include) \
>> -        -Iarch/${ARCH_DIR}/include -I`pwd`/include-compat \
>> +        $(if $(KERNELSOURCEDIR),\
>> +            -Iinclude2 -I$(KERNELSOURCEDIR)/include
>> -I$(KERNELSOURCEDIR)/arch/${ARCH_DIR}/include, \
>> +            -Iarch/${ARCH_DIR}/include) -I`pwd`/include-compat \
>>          -include include/linux/autoconf.h \
>>          -include `pwd`/$(ARCH_DIR)/external-module-compat.h
>> $(module_defines)" \
>>          "$$@"
>>   
> 
> This removes -Iarch/${ARCH_DIR}/include when KERNELSOURCEDIR is not
> defined.  What is the reason for this change?
> 

As far as I can see (I do wear my glasses today...),
-Iarch/${ARCH_DIR}/include is present in the else part of $(if).

The reason for this change is the missing arch include from the source
directory in case it's separate from the build dir (yeah, the changelog
has room for improvements).

I ran into the same issue after building and installing a recent kernel
tree with O=. The split trees SUSE leaves behind do not suffer from
this, but they also still work after the change. Same for classic
unified trees.

Jan

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