[PATCH v2] trace_printk: replace ___STR with compound literal

[Qian-Yu Lin <tiffany019230@gmail.com>]

The macro trace_printk() uses a hardcoded identifier ___STR
within a statement expression, which can lead to variable name
shadowing if a caller happens to use the same name in its scope.

Replace the hardcoded identifier with a compound literal, which
eliminates the local variable entirely and removes any shadowing
risk without requiring an extra include or helper macro.

Since trace_printk() is never nested, __UNIQUE_ID() provides no
practical benefit here. The compound literal approach is simpler
and has no compile time overhead, unlike the v1 approach which
added #include <linux/compiler.h>.

Signed-off-by: Qian-Yu Lin <tiffany019230@gmail.com>
---
 include/linux/trace_printk.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/include/linux/trace_printk.h b/include/linux/trace_printk.h
index 2670ec7f4262..7a4f6711834f 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((char[]){__stringify((__VA_ARGS__))}) > 3)			\
 		do_trace_printk(fmt, ##__VA_ARGS__);	\
 	else						\
 		trace_puts(fmt);			\
-- 
2.43.0