[dpdk-dev] [PATCH] eal/x86: fix clang build with -O0

[Thomas Monjalon <thomas.monjalon@6wind.com>]

From: Damjan Marion <damarion@cisco.com>

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 <damarion@cisco.com>
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
---
 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