From: Nathan Chancellor natechancellor@gmail.com
commit 8306b057a85ec07482da5d4b99d5c0b47af69be1 upstream.
Clang warns:
../lib/dynamic_debug.c:1034:24: warning: array comparison always evaluates to false [-Wtautological-compare] if (__start___verbose == __stop___verbose) { ^ 1 warning generated.
These are not true arrays, they are linker defined symbols, which are just addresses. Using the address of operator silences the warning and does not change the resulting assembly with either clang/ld.lld or gcc/ld (tested with diff + objdump -Dr).
Suggested-by: Nick Desaulniers ndesaulniers@google.com Signed-off-by: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Acked-by: Jason Baron jbaron@akamai.com Link: https://github.com/ClangBuiltLinux/linux/issues/894 Link: http://lkml.kernel.org/r/20200220051320.10739-1-natechancellor@gmail.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- lib/dynamic_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -984,7 +984,7 @@ static int __init dynamic_debug_init(voi int n = 0, entries = 0, modct = 0; int verbose_bytes = 0;
- if (__start___verbose == __stop___verbose) { + if (&__start___verbose == &__stop___verbose) { pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n"); return 1; }