Andrew Jones <drjones@xxxxxxxxxx> writes: > On Thu, Jan 12, 2017 at 01:29:24PM +0100, Paolo Bonzini wrote: >> >> >> On 11/01/2017 17:28, Alex Bennée wrote: >> > So we can have portable formatting of uint32_t types. However there is >> > a catch. Different compilers can use legally subtly different types >> > though so we need to probe the compiler defined intdef.h first. >> >> Interesting, what platform has long uint32_t? I thought the issue was >> whether 64-bit is long or "long long". >> >> Paolo >> >> > Signed-off-by: Alex Bennée <alex.bennee@xxxxxxxxxx> >> > --- >> > Makefile | 1 + >> > configure | 13 +++++++++++++ >> > lib/libcflat.h | 9 +++++++++ >> > 3 files changed, 23 insertions(+) >> > >> > diff --git a/Makefile b/Makefile >> > index a32333b..9822d9a 100644 >> > --- a/Makefile >> > +++ b/Makefile >> > @@ -55,6 +55,7 @@ CFLAGS += $(fomit_frame_pointer) >> > CFLAGS += $(fno_stack_protector) >> > CFLAGS += $(fno_stack_protector_all) >> > CFLAGS += $(wno_frame_address) >> > +CFLAGS += $(if $(U32_LONG_FMT),-D__U32_LONG_FMT__,) >> > >> > CXXFLAGS += $(CFLAGS) >> > >> > diff --git a/configure b/configure >> > index 995c8fa..127868c 100755 >> > --- a/configure >> > +++ b/configure >> > @@ -109,6 +109,18 @@ if [ -f $testdir/run ]; then >> > ln -fs $testdir/run $testdir-run >> > fi >> > >> > +# check if uint32_t needs a long format modifier >> > +cat << EOF > lib_test.c >> > +#include <inttypes.h> >> > +EOF >> > + >> > +$cross_prefix$cc lib_test.c -E | grep "typedef" | grep "long" | grep "uint32_t" &> /dev/null > > This won't work with cross compilers that don't have inttypes.h in their > path (like mine). How about something like Hmm good point, in my case inttypes.h came from the libnewlib-dev package. > > cat << EOF > lib_test.c > __UINT32_TYPE__ > EOF > u32_long="`aarch64-linux-gnu-gcc lib_test.c -E | awk '/unsigned/ && $2 == "long"'`" Hmm it is not clear from the docs if this is a GCCism. If it is do we care? Also the docs do say: "Some of these macros may not be defined on particular systems if GCC does not provide a stdint.h header on those systems. " > Although I feel there should be a compiler macro way to do this without > a need for configure/makefile trickery at all... I did ask our toolchain bods. They started going on about potential solutions using _Generic but I fear that might be worse in this case! > > Thanks, > drew > > >> > +exit=$? >> > +if [ $exit -eq 0 ]; then >> > + u32_long=true >> > +fi >> > +rm -f lib_test.c >> > + >> > # check for dependent 32 bit libraries >> > if [ "$arch" != "arm" ]; then >> > cat << EOF > lib_test.c >> > @@ -155,4 +167,5 @@ TEST_DIR=$testdir >> > FIRMWARE=$firmware >> > ENDIAN=$endian >> > PRETTY_PRINT_STACKS=$pretty_print_stacks >> > +U32_LONG_FMT=$u32_long >> > EOF >> > diff --git a/lib/libcflat.h b/lib/libcflat.h >> > index 380395f..e80fc50 100644 >> > --- a/lib/libcflat.h >> > +++ b/lib/libcflat.h >> > @@ -58,12 +58,21 @@ typedef _Bool bool; >> > #define true 1 >> > >> > #if __SIZEOF_LONG__ == 8 >> > +# define __PRI32_PREFIX >> > # define __PRI64_PREFIX "l" >> > # define __PRIPTR_PREFIX "l" >> > #else >> > +#if defined(__U32_LONG_FMT__) >> > +# define __PRI32_PREFIX "l" >> > +#else >> > +# define __PRI32_PREFIX >> > +#endif >> > # define __PRI64_PREFIX "ll" >> > # define __PRIPTR_PREFIX >> > #endif >> > +#define PRId32 __PRI32_PREFIX "d" >> > +#define PRIu32 __PRI32_PREFIX "u" >> > +#define PRIx32 __PRI32_PREFIX "x" >> > #define PRId64 __PRI64_PREFIX "d" >> > #define PRIu64 __PRI64_PREFIX "u" >> > #define PRIx64 __PRI64_PREFIX "x" >> > >> -- >> To unsubscribe from this list: send the line "unsubscribe kvm" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- Alex Bennée -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
