tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
After r372664 in clang, the IF_ASSIGN macro causes a couple hundred
warnings along the lines of:
kernel/trace/trace_output.c:1331:2: warning: converting the enum
constant to a boolean [-Wint-in-bool-context]
kernel/trace/trace.h:409:3: note: expanded from macro
'trace_assign_type'
IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,
^
kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN'
WARN_ON(id && (entry)->type != id); \
^
264 warnings generated.
This warning can catch issues with constructs like:
if (state == A || B)
where the developer really meant:
if (state == A || state == B)
This is currently the only occurrence of the warning in the kernel
tree across defconfig, allyesconfig, allmodconfig for arm32, arm64,
and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix
the warnings and find potential issues in the future.
Link: https://github.com/llvm/llvm-project/commit/28b38c277a2941e9e891b2db30652cfd962f070b
Link: https://github.com/ClangBuiltLinux/linux/issues/686
Link: http://lkml.kernel.org/r/20190926162258.466321-1-natechancellor@gmail.com
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed