Re: [PATCH] uapi: Make generic uapi headers compile standalone.

From: Randy Dunlap <rdunlap@infradead.org>
To: Jayant Chowdhary <jchowdhary@google.com>, linux-kernel@vger.kernel.org
Cc: akpm@linux-foundation.org, kernel-team@android.com,
	linux-kbuild@vger.kernel.org
Subject: Re: [PATCH] uapi: Make generic uapi headers compile standalone.
Date: Thu, 7 Jun 2018 17:07:01 -0700	[thread overview]
Message-ID: <b6b6dd56-c948-54e8-df95-3d170a3c1e7d@infradead.org> (raw)
In-Reply-To: <20180606231602.231326-1-jchowdhary@google.com>

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On 06/06/2018 04:16 PM, Jayant Chowdhary wrote:
> In order for static analysis tools to analyze each of the uapi headers,
> we need to enable them to compile stand-alone. Some uapi headers were
> missing dependencies which would not make them compile stand-alone in
> user-land. This patch adds those dependencies.

Hi,

Thanks for getting started on this.  I see that the kbuild robot and I were
still not able to do successful builds even after this patch is applied.
We were building different targets though.  robot was doing kernel builds
and I was doing a large "all-uapi" build.

I started on my all-uapi work about 1 week ago but haven't posted anything yet,
but it's posted (attached) below.  It's not yet up to kernel quality yet (for a
Makefile), and I have made very little progress toward a successful userspace build.

If anyone is interested, just put these 3 files in <kernel_tree>/tools/build
and then run:

make ARCH=$some_arch O=build_dir headers_check
so that the headers will be cleaned up and installed in build_dir/usr/.

Then run 'make -f all-uapi.mk'
and the userspace program with all header files found in build_dir/usr/include
will be built -- i.e., attempted (not successfully).

(note: chmod +x hdr-fix-lines.pl)

-- 
~Randy

[-- Attachment #2: all-uapi.mk --]
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# all-uapi.mk
# currently resides in tools/build/
#
# before running 'make -f all-uapi.mk',
# run (from top of kernel tree): make ARCH=arch O=dir headers_check
# so that the uapi headers will be installed.

srctree=../..
CC=gcc

all: all-uapi.h all-uapi.o

all-uapi.h: all-uapi.mk hdr-fix-lines.pl
	rm -f all-uapi.h
	touch all-uapi.h
#	find $(srctree)/xx64/usr/include/uapi -type f | grep -v \\.orig |
	find $(srctree)/xx64/usr/include -type f | grep -v \\.orig | \
		./hdr-fix-lines.pl >>all-uapi.h

all-uapi.o: all-uapi.h
	$(CC) -I../../xx64/usr/include all-uapi.c -o all-uapi.o

[-- Attachment #3: all-uapi.c --]
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// SPDX GPL 2.0
// This userspace source file pulls in all #include <uapi/*> header files
// to see what kinds of problems happen.

#include <stdio.h>
#include <stdarg.h>
#include <stdint.h>

#include <linux/posix_types.h>
#include <asm-generic/ipcbuf.h>

#include "all-uapi.h"

int main(int argc, char *argv[])
{
}

[-- Attachment #4: hdr-fix-lines.pl --]
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