From 1520e8466d683b6c5e1aa53aa65165ebd5da46cf Mon Sep 17 00:00:00 2001 From: Khem Raj Date: Mon, 19 Dec 2022 11:15:26 -0800 Subject: [PATCH] libbpf: Fix build warning on ref_ctr_off for 32-bit architectures Clang warns on 32-bit ARM on this comparision: libbpf.c:10497:18: error: result of comparison of constant 4294967296 with expression of type 'size_t' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare] if (ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS)) ~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Typecast ref_ctr_off to __u64 in the check conditional, it is false on 32bit anyways. Signed-off-by: Khem Raj Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20221219191526.296264-1-raj.khem@gmail.com --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2a82f49ce16f..a5c67a3c93c5 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -9903,7 +9903,7 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, char errmsg[STRERR_BUFSIZE]; int type, pfd; - if (ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS)) + if ((__u64)ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS)) return -EINVAL; memset(&attr, 0, attr_sz);