From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57006) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eyjBB-0008NL-AG for qemu-devel@nongnu.org; Wed, 21 Mar 2018 15:13:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eyjB7-0000TT-C2 for qemu-devel@nongnu.org; Wed, 21 Mar 2018 15:13:45 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:33744 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eyjB7-0000Su-64 for qemu-devel@nongnu.org; Wed, 21 Mar 2018 15:13:41 -0400 Date: Wed, 21 Mar 2018 21:13:25 +0200 From: "Michael S. Tsirkin" Message-ID: <20180321211301-mutt-send-email-mst@kernel.org> References: <1521645545-247351-1-git-send-email-mst@redhat.com> <1521645545-247351-2-git-send-email-mst@redhat.com> <20180321153651.GS8551@redhat.com> <20180321174022-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH for-2.12 2/2] make: switch from -I to -iquote List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Marcel Apfelbaum Cc: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , qemu-devel@nongnu.org, Yuval Shaia , Paolo Bonzini , Yang Zhong , Philippe =?iso-8859-1?Q?Mathieu-Daud=C3=A9?= , Richard Henderson , Peter Maydell , Gerd Hoffmann , Fam Zheng , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Stefan Hajnoczi , Stefan Weil On Wed, Mar 21, 2018 at 06:40:23PM +0200, Marcel Apfelbaum wrote: > On 21/03/2018 18:02, Michael S. Tsirkin wrote: > > On Wed, Mar 21, 2018 at 03:36:51PM +0000, Daniel P. Berrang=E9 wrote: > >> On Wed, Mar 21, 2018 at 05:22:07PM +0200, Michael S. Tsirkin wrote: > >>> Our rule right now is to use <> for external headers, > >>> "" for internal ones. The idea was to avoid conflicts > >>> between e.g. a system file named and an > >>> internal one by the same name. > >>> > >>> Unfortunately we use -I compiler flag so it does not > >>> help: a system file doing #include will > >>> still pick up ours first. > >> > >> Has that actually hit you practice ? I'm wondering if this > >> is just theoretical in which case it could wait till 2.13 > >> since this scenario has existed in QEMU along time, or > >> a real problem right now requiring fix in 2.12. > >=20 > > It's borderline. > >=20 > > In particular there is at least one instance where we already have a > > conflict (yes, there are probably other ways to address this, but > > I consider them less robust): > >=20 > > util/getauxval.c:#include > > /usr/include/sys/auxv.h:#include > >=20 > > So it really does build by luck. > >=20 > >=20 > >>> To fix, switch to -iquote which is supported by both > >>> gcc and clang and only affects #include "" directives. > >> > >> Fine since we don't support anything other than > >> gcc and clang. I'm assuming -iquote has been supported > >> by these two compilers for a long time though ? The GCC > >> docs annoyingly don't ever mention what release features > >> appear in :-( > >=20 > > Judging by git log output: > >=20 > > For clang it appears to be there since 2007 that's pretty > > close to day 1. > >=20 > > gcc's log is better documented, it's been there since 2004-05-03 > >=20 > >>> > >>> As a side effect, this catches any future uses of > >>> #include <> for internal headers. > >>> > >>> Suggested-by: Stefan Weil > >>> Signed-off-by: Michael S. Tsirkin > >>> --- > >> > >> Reviewed-by: Daniel P. Berrang=E9 > >=20 > >=20 > > Thanks! > >=20 >=20 > Hi Michael, > Should I add this patch to the RDMA pull request? >=20 > Thanks, > Marcel Go ahead and add both of them pls. >=20 > >> > >>> > >>> I still think we want to switch to a more formal rule such as qemu/ > >>> prefix for all includes down the road, but this will at least catch= any > >>> scheme violations from creeping in meanwhile. > >>> > >>> > >>> configure | 16 ++++++++-------- > >>> rules.mak | 2 +- > >>> Makefile.target | 4 ++-- > >>> 3 files changed, 11 insertions(+), 11 deletions(-) > >>> > >>> diff --git a/configure b/configure > >>> index af72fc8..23a4f3b 100755 > >>> --- a/configure > >>> +++ b/configure > >>> @@ -534,7 +534,7 @@ QEMU_CFLAGS=3D"-fno-strict-aliasing -fno-common= -fwrapv $QEMU_CFLAGS" > >>> QEMU_CFLAGS=3D"-Wall -Wundef -Wwrite-strings -Wmissing-prototypes = $QEMU_CFLAGS" > >>> QEMU_CFLAGS=3D"-Wstrict-prototypes -Wredundant-decls $QEMU_CFLAGS" > >>> QEMU_CFLAGS=3D"-D_GNU_SOURCE -D_FILE_OFFSET_BITS=3D64 -D_LARGEFILE= _SOURCE $QEMU_CFLAGS" > >>> -QEMU_INCLUDES=3D"-I. -I\$(SRC_PATH) -I\$(SRC_PATH)/accel/tcg -I\$(= SRC_PATH)/include" > >>> +QEMU_INCLUDES=3D"-iquote . -iquote \$(SRC_PATH) -iquote \$(SRC_PAT= H)/accel/tcg -iquote \$(SRC_PATH)/include" > >>> if test "$debug_info" =3D "yes"; then > >>> CFLAGS=3D"-g $CFLAGS" > >>> LDFLAGS=3D"-g $LDFLAGS" > >>> @@ -6560,19 +6560,19 @@ if test "$vxhs" =3D "yes" ; then > >>> fi > >>> =20 > >>> if test "$tcg_interpreter" =3D "yes"; then > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/tci $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/tci $QEMU_INCLUDES" > >>> elif test "$ARCH" =3D "sparc64" ; then > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/sparc $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/sparc $QEMU_INCLUDES" > >>> elif test "$ARCH" =3D "s390x" ; then > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/s390 $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/s390 $QEMU_INCLUDES" > >>> elif test "$ARCH" =3D "x86_64" -o "$ARCH" =3D "x32" ; then > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/i386 $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/i386 $QEMU_INCLUDES" > >>> elif test "$ARCH" =3D "ppc64" ; then > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/ppc $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/ppc $QEMU_INCLUDES" > >>> else > >>> - QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg/\$(ARCH) $QEMU_INCLUDES" > >>> + QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg/\$(ARCH) $QEMU_INCLUDE= S" > >>> fi > >>> -QEMU_INCLUDES=3D"-I\$(SRC_PATH)/tcg $QEMU_INCLUDES" > >>> +QEMU_INCLUDES=3D"-iquote \$(SRC_PATH)/tcg $QEMU_INCLUDES" > >>> =20 > >>> echo "TOOLS=3D$tools" >> $config_host_mak > >>> echo "ROMS=3D$roms" >> $config_host_mak > >>> diff --git a/rules.mak b/rules.mak > >>> index 6e94333..93a0702 100644 > >>> --- a/rules.mak > >>> +++ b/rules.mak > >>> @@ -29,7 +29,7 @@ QEMU_DGFLAGS +=3D -MMD -MP -MT $@ -MF $(@D)/$(*F)= .d > >>> # dir, one absolute and the other relative to the compiler working > >>> # directory. These are the same for target-independent files, but > >>> # different for target-dependent ones. > >>> -QEMU_LOCAL_INCLUDES =3D -I$(BUILD_DIR)/$(@D) -I$(@D) > >>> +QEMU_LOCAL_INCLUDES =3D -iquote $(BUILD_DIR)/$(@D) -iquote $(@D) > >>> =20 > >>> WL_U :=3D -Wl,-u, > >>> find-symbols =3D $(if $1, $(sort $(shell $(NM) -P -g $1 | $2))) > >>> diff --git a/Makefile.target b/Makefile.target > >>> index 6549481..d0ec77a 100644 > >>> --- a/Makefile.target > >>> +++ b/Makefile.target > >>> @@ -11,9 +11,9 @@ $(call set-vpath, $(SRC_PATH):$(BUILD_DIR)) > >>> ifdef CONFIG_LINUX > >>> QEMU_CFLAGS +=3D -I../linux-headers > >>> endif > >>> -QEMU_CFLAGS +=3D -I.. -I$(SRC_PATH)/target/$(TARGET_BASE_ARCH) -DN= EED_CPU_H > >>> +QEMU_CFLAGS +=3D -iquote .. -iquote $(SRC_PATH)/target/$(TARGET_BA= SE_ARCH) -DNEED_CPU_H > >>> =20 > >>> -QEMU_CFLAGS+=3D-I$(SRC_PATH)/include > >>> +QEMU_CFLAGS+=3D-iquote $(SRC_PATH)/include > >>> =20 > >>> ifdef CONFIG_USER_ONLY > >>> # user emulator name > >>> --=20 > >>> MST > >>> > >> > >> Regards, > >> Daniel > >> --=20 > >> |: https://berrange.com -o- https://www.flickr.com/photos/db= errange :| > >> |: https://libvirt.org -o- https://fstop138.berra= nge.com :| > >> |: https://entangle-photo.org -o- https://www.instagram.com/db= errange :|