On 14.01.2019 19:46, Richardson, Bruce wrote: > > >> -----Original Message----- >> From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Ilya Maximets >> Sent: Monday, January 14, 2019 4:15 PM >> To: dev@dpdk.org; Thomas Monjalon <tho...@monjalon.net> >> Cc: Pavan Nikhilesh <pbhagavat...@marvell.com>; Ilya Maximets >> <i.maxim...@samsung.com>; sta...@dpdk.org >> Subject: [dpdk-dev] [PATCH] eal: fix build of external apps with clang on >> armv8 >> >> In case DPDK built using GCC, RTE_TOOLCHAIN_CLANG is not defined. >> But 'rte_atomic.h' is a generic header that included to the external apps >> like OVS while building with DPDK. As a result, clang build of OVS fails >> on ARMv8 if DPDK built using gcc: >> >> include/generic/rte_atomic.h:215:9: error: >> implicit declaration of function '__atomic_exchange_2' >> is invalid in C99 >> include/generic/rte_atomic.h:494:9: error: >> implicit declaration of function '__atomic_exchange_4' >> is invalid in C99 >> include/generic/rte_atomic.h:772:9: error: >> implicit declaration of function '__atomic_exchange_8' >> is invalid in C99 >> >> We need to check for current compiler, not the compiler used for DPDK >> build. >> >> Fixes: 7bdccb93078e ("eal: fix ARM build with clang") >> Cc: sta...@dpdk.org >> >> Signed-off-by: Ilya Maximets <i.maxim...@samsung.com> >> --- >> lib/librte_eal/common/include/generic/rte_atomic.h | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/lib/librte_eal/common/include/generic/rte_atomic.h >> b/lib/librte_eal/common/include/generic/rte_atomic.h >> index b99ba4688..d0c464fb1 100644 >> --- a/lib/librte_eal/common/include/generic/rte_atomic.h >> +++ b/lib/librte_eal/common/include/generic/rte_atomic.h >> @@ -212,7 +212,7 @@ rte_atomic16_exchange(volatile uint16_t *dst, uint16_t >> val); static inline uint16_t rte_atomic16_exchange(volatile uint16_t >> *dst, uint16_t val) { -#if defined(RTE_ARCH_ARM64) && >> defined(RTE_TOOLCHAIN_CLANG) >> +#if defined(RTE_ARCH_ARM64) && defined(__clang__) >> return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST); #else >> return __atomic_exchange_2(dst, val, __ATOMIC_SEQ_CST); @@ -495,7 >> +495,7 @@ rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val); >> static inline uint32_t rte_atomic32_exchange(volatile uint32_t *dst, >> uint32_t val) { -#if defined(RTE_ARCH_ARM64) && >> defined(RTE_TOOLCHAIN_CLANG) >> +#if defined(RTE_ARCH_ARM64) && defined(__clang__) >> return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST); #else >> return __atomic_exchange_4(dst, val, __ATOMIC_SEQ_CST); @@ -777,7 >> +777,7 @@ rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val); >> static inline uint64_t rte_atomic64_exchange(volatile uint64_t *dst, >> uint64_t val) { -#if defined(RTE_ARCH_ARM64) && >> defined(RTE_TOOLCHAIN_CLANG) >> +#if defined(RTE_ARCH_ARM64) && defined(__clang__) >> return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST); #else >> return __atomic_exchange_8(dst, val, __ATOMIC_SEQ_CST); >> -- >> 2.17.1 > > Is this really architecture-specific? Would the same issue not occur on e.g. > x86 or PPC? >
Yes. I looked a bit deeper and found that x86 build is also broken. We have not encountered this problem earlier on other platforms because CONFIG_RTE_FORCE_INTRINSICS enabled by default only for armv8. I've sent a patch: http://patches.dpdk.org/patch/49829/ Best regards, Ilya Maximets.
