|WARNING| pw156001 [PATCH v3 2/2] virtio: simplify use of pragmas

[checkpatch@dpdk.org]

Test-Label: checkpatch
Test-Status: WARNING
http://dpdk.org/patch/156001

_coding style issues_


CHECK:CAMELCASE: Avoid CamelCase: <_Pragma>
#120: FILE: drivers/net/virtio/virtio_rxtx_packed.h:74:
+#define virtio_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \

ERROR:COMPLEX_MACRO: Macros with complex values should be enclosed in parentheses
#120: FILE: drivers/net/virtio/virtio_rxtx_packed.h:74:
+#define virtio_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \
 	for (iter = val; iter < size; iter++)

BUT SEE:

   do {} while (0) advice is over-stated in a few situations:

   The more obvious case is macros, like MODULE_PARM_DESC, invoked at
   file-scope, where C disallows code (it must be in functions).  See
   $exceptions if you have one to add by name.

   More troublesome is declarative macros used at top of new scope,
   like DECLARE_PER_CPU.  These might just compile with a do-while-0
   wrapper, but would be incorrect.  Most of these are handled by
   detecting struct,union,etc declaration primitives in $exceptions.

   Theres also macros called inside an if (block), which "return" an
   expression.  These cannot do-while, and need a ({}) wrapper.

   Enjoy this qualification while we work to improve our heuristics.

CHECK:MACRO_ARG_REUSE: Macro argument reuse 'iter' - possible side-effects?
#120: FILE: drivers/net/virtio/virtio_rxtx_packed.h:74:
+#define virtio_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \
 	for (iter = val; iter < size; iter++)

CHECK:MACRO_ARG_PRECEDENCE: Macro argument 'size' may be better as '(size)' to avoid precedence issues
#120: FILE: drivers/net/virtio/virtio_rxtx_packed.h:74:
+#define virtio_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \
 	for (iter = val; iter < size; iter++)

CHECK:MACRO_ARG_REUSE: Macro argument reuse 'iter' - possible side-effects?
#123: FILE: drivers/net/virtio/virtio_rxtx_packed.h:77:
+#define virtio_for_each_try_unroll(iter, val, num) \
+	for (iter = val; iter < num; iter++)

CHECK:MACRO_ARG_PRECEDENCE: Macro argument 'num' may be better as '(num)' to avoid precedence issues
#123: FILE: drivers/net/virtio/virtio_rxtx_packed.h:77:
+#define virtio_for_each_try_unroll(iter, val, num) \
+	for (iter = val; iter < num; iter++)

ERROR:COMPLEX_MACRO: Macros with complex values should be enclosed in parentheses
#165: FILE: lib/vhost/vhost.h:76:
+#define vhost_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \
+	for (iter = val; iter < size; iter++)

BUT SEE:

   do {} while (0) advice is over-stated in a few situations:

   The more obvious case is macros, like MODULE_PARM_DESC, invoked at
   file-scope, where C disallows code (it must be in functions).  See
   $exceptions if you have one to add by name.

   More troublesome is declarative macros used at top of new scope,
   like DECLARE_PER_CPU.  These might just compile with a do-while-0
   wrapper, but would be incorrect.  Most of these are handled by
   detecting struct,union,etc declaration primitives in $exceptions.

   Theres also macros called inside an if (block), which "return" an
   expression.  These cannot do-while, and need a ({}) wrapper.

   Enjoy this qualification while we work to improve our heuristics.

total: 2 errors, 0 warnings, 69 lines checked