diff options
| author | Qian-Yu Lin <tiffany019230@gmail.com> | 2026-05-02 10:55:34 +0300 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-05-22 01:03:06 +0300 |
| commit | 04fcbcf2dfe6a3fadc50b0f925c0b757386b82f8 (patch) | |
| tree | cf41715dff04d960c2cb130ac845bcf137a0ce63 /include/linux | |
| parent | 9764e731ef6abacdfc00d914061d4d900e302670 (diff) | |
| download | linux-04fcbcf2dfe6a3fadc50b0f925c0b757386b82f8.tar.xz | |
tracing: Remove local variable for argument detection from trace_printk()
The trace_printk() macro uses a local variable _______STR to detect
whether variadic arguments are present. This name can shadow outer
variables.
Replace the local variable with sizeof applied directly to the
stringified arguments:
if (sizeof __stringify((__VA_ARGS__)) > 3)
This eliminates the shadowing risk entirely without introducing
any additional includes or local variables.
Verified with objdump on samples/trace_printk that all four cases
branch correctly: __trace_bputs, __trace_puts, __trace_bprintk,
and __trace_printk.
Link: https://patch.msgid.link/20260502075535.34997-1-tiffany019230@gmail.com
Suggested-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Qian-Yu Lin <tiffany019230@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/trace_printk.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/include/linux/trace_printk.h b/include/linux/trace_printk.h index 2670ec7f4262..3d54f440dccf 100644 --- a/include/linux/trace_printk.h +++ b/include/linux/trace_printk.h @@ -86,8 +86,7 @@ do { \ #define trace_printk(fmt, ...) \ do { \ - char _______STR[] = __stringify((__VA_ARGS__)); \ - if (sizeof(_______STR) > 3) \ + if (sizeof __stringify((__VA_ARGS__)) > 3) \ do_trace_printk(fmt, ##__VA_ARGS__); \ else \ trace_puts(fmt); \ |