From 6e042492a272bdc507d37982b890dc5266d5bb01 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 8 Apr 2019 23:26:23 +0200 Subject: [PATCH] s390: avoid __builtin_return_address(n) on clang llvm on s390 has problems with __builtin_return_address(n), with n>0, this results in a somewhat cryptic error message: fatal error: error in backend: Unsupported stack frame traversal count To work around it, use the direct return address directly. This is probably not ideal here, but gets things to compile and should only lead to inferior reporting, not to misbehavior of the generated code. Link: https://bugs.llvm.org/show_bug.cgi?id=41424 Signed-off-by: Arnd Bergmann Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/ftrace.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 5a3c95b119527..6e0ed03387854 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -13,7 +13,12 @@ #ifndef __ASSEMBLY__ +#ifdef CONFIG_CC_IS_CLANG +/* https://bugs.llvm.org/show_bug.cgi?id=41424 */ +#define ftrace_return_address(n) 0UL +#else #define ftrace_return_address(n) __builtin_return_address(n) +#endif void _mcount(void); void ftrace_caller(void); -- 2.39.5