[dpdk-dev] [PATCH] eal/x86: fix clang build with -O0
2016-06-03 10:16, Olivier MATZ: > On 06/03/2016 10:15 AM, Thomas Monjalon wrote: > > From: Damjan Marion > > > > Clang seems to have a bug with asm inside inline function rte_xabort(): > > > > rte_rtm.h:56:15: error: invalid operand for inline asm constraint 'i' > > asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); > > ^ > > > > It is seen only when building with EXTRA_CFLAGS=-O0. > > > > The workaround is to replace the inline function by a macro. > > > > Fixes: ba7468997ea6 ("spinlock: add HTM lock elision for x86") > > > > Signed-off-by: Damjan Marion > > Signed-off-by: Thomas Monjalon > > Generally speaking, it's not a good idea to replace a static inline by a > macro because it relaxes type checking. Looks ok in that case to > workaround the clang issue. > > Acked-by: Olivier Matz Thanks, This patch has been appplied very quickly for the purpose of a live demo at a VPP event: https://wiki.fd.io/view/Events
[dpdk-dev] [PATCH] eal/x86: fix clang build with -O0
Hi Thomas, On 06/03/2016 10:15 AM, Thomas Monjalon wrote: > From: Damjan Marion > > Clang seems to have a bug with asm inside inline function rte_xabort(): > > rte_rtm.h:56:15: error: invalid operand for inline asm constraint 'i' > asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); > ^ > > It is seen only when building with EXTRA_CFLAGS=-O0. > > The workaround is to replace the inline function by a macro. > > Fixes: ba7468997ea6 ("spinlock: add HTM lock elision for x86") > > Signed-off-by: Damjan Marion > Signed-off-by: Thomas Monjalon > --- > lib/librte_eal/common/include/arch/x86/rte_rtm.h | 9 - > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/lib/librte_eal/common/include/arch/x86/rte_rtm.h > b/lib/librte_eal/common/include/arch/x86/rte_rtm.h > index d935641..0649f79 100644 > --- a/lib/librte_eal/common/include/arch/x86/rte_rtm.h > +++ b/lib/librte_eal/common/include/arch/x86/rte_rtm.h > @@ -50,11 +50,10 @@ void rte_xend(void) >asm volatile(".byte 0x0f,0x01,0xd5" ::: "memory"); > } > > -static __attribute__((__always_inline__)) inline > -void rte_xabort(const unsigned int status) > -{ > - asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); > -} > +/* not an inline function to workaround a clang bug with -O0 */ > +#define rte_xabort(status) do { \ > + asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); \ > +} while (0) > > static __attribute__((__always_inline__)) inline > int rte_xtest(void) > Generally speaking, it's not a good idea to replace a static inline by a macro because it relaxes type checking. Looks ok in that case to workaround the clang issue. Acked-by: Olivier Matz
[dpdk-dev] [PATCH] eal/x86: fix clang build with -O0
From: Damjan MarionClang seems to have a bug with asm inside inline function rte_xabort(): rte_rtm.h:56:15: error: invalid operand for inline asm constraint 'i' asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); ^ It is seen only when building with EXTRA_CFLAGS=-O0. The workaround is to replace the inline function by a macro. Fixes: ba7468997ea6 ("spinlock: add HTM lock elision for x86") Signed-off-by: Damjan Marion Signed-off-by: Thomas Monjalon --- lib/librte_eal/common/include/arch/x86/rte_rtm.h | 9 - 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/lib/librte_eal/common/include/arch/x86/rte_rtm.h b/lib/librte_eal/common/include/arch/x86/rte_rtm.h index d935641..0649f79 100644 --- a/lib/librte_eal/common/include/arch/x86/rte_rtm.h +++ b/lib/librte_eal/common/include/arch/x86/rte_rtm.h @@ -50,11 +50,10 @@ void rte_xend(void) asm volatile(".byte 0x0f,0x01,0xd5" ::: "memory"); } -static __attribute__((__always_inline__)) inline -void rte_xabort(const unsigned int status) -{ - asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); -} +/* not an inline function to workaround a clang bug with -O0 */ +#define rte_xabort(status) do { \ + asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory"); \ +} while (0) static __attribute__((__always_inline__)) inline int rte_xtest(void) -- 2.7.0