From: Eli Britstein <elibr@nvidia.com>
Date: Thu, 15 Oct 2020 15:10:17 +0000 (+0000)
Subject: eal: fix build with conflicting libc variable memory_order
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=057d9a92f0a9aa07dd820669d4a07b325661929f;p=dpdk.git

eal: fix build with conflicting libc variable memory_order

The cited commit introduced functions with 'int memory_order' argument.
The C11 standard section 7.17.1.4 defines 'memory_order' as the
"enumerated type whose enumerators identify memory ordering constraints".

A compilation error occurs:
error: declaration of 'memory_order' shadows a global declaration
    [-Werror=shadow]
     rte_atomic_thread_fence(int memory_order)

This issue was hit when trying to compile OVS with gcc 4.8.5. This
compiler version does not provide stdatomic.h, so enum memory_order is
redefined in OVS code.
In another case, if the compiler does provide stdatomic.h header,
passing -Wsystem-headers in the CFLAGS will also cause that failure.

Fix it by changing the argument name 'memory_order' to 'memorder'.

Fixes: 672a15056380 ("eal: add wrapper for C11 atomic thread fence")

Signed-off-by: Eli Britstein <elibr@nvidia.com>
Reviewed-by: Asaf Penso <asafp@nvidia.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
---

diff --git a/lib/librte_eal/arm/include/rte_atomic_32.h b/lib/librte_eal/arm/include/rte_atomic_32.h
index 9d0568d497..fe48ab428e 100644
--- a/lib/librte_eal/arm/include/rte_atomic_32.h
+++ b/lib/librte_eal/arm/include/rte_atomic_32.h
@@ -34,9 +34,9 @@ extern "C" {
 #define rte_io_rmb() rte_rmb()
 
 static __rte_always_inline void
-rte_atomic_thread_fence(int memory_order)
+rte_atomic_thread_fence(int memorder)
 {
-	__atomic_thread_fence(memory_order);
+	__atomic_thread_fence(memorder);
 }
 
 #ifdef __cplusplus
diff --git a/lib/librte_eal/arm/include/rte_atomic_64.h b/lib/librte_eal/arm/include/rte_atomic_64.h
index c518559bc9..20dd6c75dd 100644
--- a/lib/librte_eal/arm/include/rte_atomic_64.h
+++ b/lib/librte_eal/arm/include/rte_atomic_64.h
@@ -38,9 +38,9 @@ extern "C" {
 #define rte_io_rmb() rte_rmb()
 
 static __rte_always_inline void
-rte_atomic_thread_fence(int memory_order)
+rte_atomic_thread_fence(int memorder)
 {
-	__atomic_thread_fence(memory_order);
+	__atomic_thread_fence(memorder);
 }
 
 /*------------------------ 128 bit atomic operations -------------------------*/
diff --git a/lib/librte_eal/include/generic/rte_atomic.h b/lib/librte_eal/include/generic/rte_atomic.h
index d1255b2d8c..276272f40b 100644
--- a/lib/librte_eal/include/generic/rte_atomic.h
+++ b/lib/librte_eal/include/generic/rte_atomic.h
@@ -122,7 +122,7 @@ static inline void rte_io_rmb(void);
 /**
  * Synchronization fence between threads based on the specified memory order.
  */
-static inline void rte_atomic_thread_fence(int memory_order);
+static inline void rte_atomic_thread_fence(int memorder);
 
 /*------------------------- 16 bit atomic operations -------------------------*/
 
diff --git a/lib/librte_eal/ppc/include/rte_atomic.h b/lib/librte_eal/ppc/include/rte_atomic.h
index a91989930b..6a7e65210c 100644
--- a/lib/librte_eal/ppc/include/rte_atomic.h
+++ b/lib/librte_eal/ppc/include/rte_atomic.h
@@ -37,9 +37,9 @@ extern "C" {
 #define rte_io_rmb() rte_rmb()
 
 static __rte_always_inline void
-rte_atomic_thread_fence(int memory_order)
+rte_atomic_thread_fence(int memorder)
 {
-	__atomic_thread_fence(memory_order);
+	__atomic_thread_fence(memorder);
 }
 
 /*------------------------- 16 bit atomic operations -------------------------*/
diff --git a/lib/librte_eal/x86/include/rte_atomic.h b/lib/librte_eal/x86/include/rte_atomic.h
index b7d6b06ddf..915afd9d27 100644
--- a/lib/librte_eal/x86/include/rte_atomic.h
+++ b/lib/librte_eal/x86/include/rte_atomic.h
@@ -87,12 +87,12 @@ rte_smp_mb(void)
  * used instead.
  */
 static __rte_always_inline void
-rte_atomic_thread_fence(int memory_order)
+rte_atomic_thread_fence(int memorder)
 {
-	if (memory_order == __ATOMIC_SEQ_CST)
+	if (memorder == __ATOMIC_SEQ_CST)
 		rte_smp_mb();
 	else
-		__atomic_thread_fence(memory_order);
+		__atomic_thread_fence(memorder);
 }
 
 /*------------------------- 16 bit atomic operations -------------------------*/