]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
authorNathan Chancellor <natechancellor@gmail.com>
Thu, 26 Sep 2019 16:22:59 +0000 (09:22 -0700)
committerSteven Rostedt (VMware) <rostedt@goodmis.org>
Sat, 28 Sep 2019 21:13:39 +0000 (17:13 -0400)
commit968e5170939662341242812b9c82ef51cf140a33
tree55b5f965485179f55046d23c82426240baf62f4d
parentd2aea95a1a4d195d939d16303700921be318a2b9
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>
kernel/trace/trace.h