On 31 January 2017 at 17:40, Markus Armbruster <arm...@redhat.com> wrote: > Peter Maydell <peter.mayd...@linaro.org> writes: > >> We already require gcc 4.1 or newer (for the atomic >> support), so the fallback codepaths for older gcc >> versions than that are now dead code and we can >> just delete them. >> >> NB: clang reports itself as gcc 4.2 (regardless of >> clang version), so clang won't be using the fallbacks >> either. >> >> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> >> --- >> For compatibility with clang we should probably try to avoid >> using QEMU_GNUC_PREREQ() and instead have something in >> compiler.h that abstracts away whether the test for "does >> the compiler support feature foo" is via a GCC version >> check or a clang __has_feature or whatever. > > Yes, testing for feature is better than testing a version. > > This patch reduces use of QEMU_GNUC_PREREQ roughly by half. Good. > >> >> >> include/qemu/compiler.h | 8 --- >> include/qemu/host-utils.h | 121 >> ---------------------------------------------- >> tcg/arm/tcg-target.h | 7 --- >> 3 files changed, 136 deletions(-) >> >> diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h >> index 157698b..fc12e49 100644 >> --- a/include/qemu/compiler.h >> +++ b/include/qemu/compiler.h >> @@ -24,17 +24,9 @@ >> >> #define QEMU_NORETURN __attribute__ ((__noreturn__)) >> >> -#if QEMU_GNUC_PREREQ(3, 4) >> #define QEMU_WARN_UNUSED_RESULT __attribute__((warn_unused_result)) >> -#else >> -#define QEMU_WARN_UNUSED_RESULT >> -#endif > > Should we inline this macro?
We have attributes which we wrap in QEMU_ macros already even though they always expand to the same thing: QEMU_NORETURN and QEMU_ALIGNED. I'm happy to leave these to follow that pattern. (If you wanted to send a patch series that uninlined all of those then I wouldn't hugely object to it, but I think it touches enough files that it's a separate thing from removing the #if guards that this patch does.) thanks -- PMM
