On Wed, Mar 27, 2019 at 11:53:30AM -0400, Steven Rostedt wrote: > On Tue, 26 Mar 2019 01:23:03 +0530 > Hariprasad Kelam <hariprasad.kelam@xxxxxxxxx> wrote: > > > This patch fixes below spare errors. > > > > Sparse error: > > make C=2 CF=-D__CHECK_ENDIAN__ M=net/core > > ./include/trace/events/neigh.h:73:1: error: directive in argument list > > ./include/trace/events/neigh.h:78:1: error: directive in argument list > > ./include/trace/events/neigh.h:150:1: error: directive in argument list > > ./include/trace/events/neigh.h:155:1: error: directive in argument list > > > > I have nothing really against these patches, but why is the current > code considered wrong? > > Note, TRACE_EVENTS() are "special macros". They hold structure > definitions and full code inside the argument list. There should be no > reason that this is causing a warning. The problem is that #ifdefs at line 73 & 150 are inside TRACE_EVENT()'s invocation and this is undefined behaviour. From the standard: ... If there are sequences of preprocessing tokens within the list of arguments that would otherwise act as preprocessing directives, the behavior is undefined. [C90 6.8.3, C99 & C11 6.10.3p11] GCC can handle it (and sparse too) but yes sparse complains about it. -- Luc Van Oostenryck
