clang-18.1.3 on Ubuntu 24.04.2 reports warning: thread_loop.c:41:23: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths] 41 | : /* in */ [i] "r" (i), [len] "r" (len) | ^ thread_loop.c:37:8: note: use constraint modifier "w" 37 | "add %[i], %[i], #1\n" | ^~~~ | %w[i] thread_loop.c:41:23: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths] 41 | : /* in */ [i] "r" (i), [len] "r" (len) | ^ thread_loop.c:37:14: note: use constraint modifier "w" 37 | "add %[i], %[i], #1\n" | ^~~~ | %w[i] thread_loop.c:41:23: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths] 41 | : /* in */ [i] "r" (i), [len] "r" (len) | ^ thread_loop.c:38:8: note: use constraint modifier "w" 38 | "cmp %[i], %[len]\n" | ^~~~ | %w[i] thread_loop.c:41:38: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths] 41 | : /* in */ [i] "r" (i), [len] "r" (len) | ^ thread_loop.c:38:14: note: use constraint modifier "w" 38 | "cmp %[i], %[len]\n" | ^~~~~~ | %w[len] Use the modifier "w" for 32-bit register access. Signed-off-by: Leo Yan --- tools/perf/tests/shell/coresight/thread_loop/thread_loop.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/tests/shell/coresight/thread_loop/thread_loop.c b/tools/perf/tests/shell/coresight/thread_loop/thread_loop.c index e05a559253ca9d9366ad321d520349042fb07fca..86f3f548b00631682767665fc5e9d5b8551a3634 100644 --- a/tools/perf/tests/shell/coresight/thread_loop/thread_loop.c +++ b/tools/perf/tests/shell/coresight/thread_loop/thread_loop.c @@ -34,8 +34,8 @@ static void *thrfn(void *arg) } asm volatile( "loop:\n" - "add %[i], %[i], #1\n" - "cmp %[i], %[len]\n" + "add %w[i], %w[i], #1\n" + "cmp %w[i], %w[len]\n" "blt loop\n" : /* out */ : /* in */ [i] "r" (i), [len] "r" (len) -- 2.34.1