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. Berrangé 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 <trace.h> and an > >>> internal one by the same name. > >>> > >>> Unfortunately we use -I compiler flag so it does not > >>> help: a system file doing #include <trace.h> 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. > > > > It's borderline. > > > > 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): > > > > util/getauxval.c:#include <sys/auxv.h> > > /usr/include/sys/auxv.h:#include <elf.h> > > > > So it really does build by luck. > > > > > >>> 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 :-( > > > > Judging by git log output: > > > > For clang it appears to be there since 2007 that's pretty > > close to day 1. > > > > gcc's log is better documented, it's been there since 2004-05-03 > > > >>> > >>> As a side effect, this catches any future uses of > >>> #include <> for internal headers. > >>> > >>> Suggested-by: Stefan Weil <s...@weilnetz.de> > >>> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > >>> --- > >> > >> Reviewed-by: Daniel P. Berrangé <berra...@redhat.com> > > > > > > Thanks! > > > > Hi Michael, > Should I add this patch to the RDMA pull request? > > Thanks, > Marcel
Go ahead and add both of them pls. > > >> > >>> > >>> 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="-fno-strict-aliasing -fno-common -fwrapv > >>> $QEMU_CFLAGS" > >>> QEMU_CFLAGS="-Wall -Wundef -Wwrite-strings -Wmissing-prototypes > >>> $QEMU_CFLAGS" > >>> QEMU_CFLAGS="-Wstrict-prototypes -Wredundant-decls $QEMU_CFLAGS" > >>> QEMU_CFLAGS="-D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE > >>> $QEMU_CFLAGS" > >>> -QEMU_INCLUDES="-I. -I\$(SRC_PATH) -I\$(SRC_PATH)/accel/tcg > >>> -I\$(SRC_PATH)/include" > >>> +QEMU_INCLUDES="-iquote . -iquote \$(SRC_PATH) -iquote > >>> \$(SRC_PATH)/accel/tcg -iquote \$(SRC_PATH)/include" > >>> if test "$debug_info" = "yes"; then > >>> CFLAGS="-g $CFLAGS" > >>> LDFLAGS="-g $LDFLAGS" > >>> @@ -6560,19 +6560,19 @@ if test "$vxhs" = "yes" ; then > >>> fi > >>> > >>> if test "$tcg_interpreter" = "yes"; then > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/tci $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/tci $QEMU_INCLUDES" > >>> elif test "$ARCH" = "sparc64" ; then > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/sparc $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/sparc $QEMU_INCLUDES" > >>> elif test "$ARCH" = "s390x" ; then > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/s390 $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/s390 $QEMU_INCLUDES" > >>> elif test "$ARCH" = "x86_64" -o "$ARCH" = "x32" ; then > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/i386 $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/i386 $QEMU_INCLUDES" > >>> elif test "$ARCH" = "ppc64" ; then > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/ppc $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/ppc $QEMU_INCLUDES" > >>> else > >>> - QEMU_INCLUDES="-I\$(SRC_PATH)/tcg/\$(ARCH) $QEMU_INCLUDES" > >>> + QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg/\$(ARCH) $QEMU_INCLUDES" > >>> fi > >>> -QEMU_INCLUDES="-I\$(SRC_PATH)/tcg $QEMU_INCLUDES" > >>> +QEMU_INCLUDES="-iquote \$(SRC_PATH)/tcg $QEMU_INCLUDES" > >>> > >>> echo "TOOLS=$tools" >> $config_host_mak > >>> echo "ROMS=$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 += -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 = -I$(BUILD_DIR)/$(@D) -I$(@D) > >>> +QEMU_LOCAL_INCLUDES = -iquote $(BUILD_DIR)/$(@D) -iquote $(@D) > >>> > >>> WL_U := -Wl,-u, > >>> find-symbols = $(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 += -I../linux-headers > >>> endif > >>> -QEMU_CFLAGS += -I.. -I$(SRC_PATH)/target/$(TARGET_BASE_ARCH) -DNEED_CPU_H > >>> +QEMU_CFLAGS += -iquote .. -iquote $(SRC_PATH)/target/$(TARGET_BASE_ARCH) > >>> -DNEED_CPU_H > >>> > >>> -QEMU_CFLAGS+=-I$(SRC_PATH)/include > >>> +QEMU_CFLAGS+=-iquote $(SRC_PATH)/include > >>> > >>> ifdef CONFIG_USER_ONLY > >>> # user emulator name > >>> -- > >>> MST > >>> > >> > >> Regards, > >> Daniel > >> -- > >> |: https://berrange.com -o- > >> https://www.flickr.com/photos/dberrange :| > >> |: https://libvirt.org -o- > >> https://fstop138.berrange.com :| > >> |: https://entangle-photo.org -o- > >> https://www.instagram.com/dberrange :|