ARM: 8900/1: UNWINDER_FRAME_POINTER implementation for Clang

The stackframe setup when compiled with clang is different.
Since the stack unwinder expects the gcc stackframe setup it
fails to print backtraces. This patch adds support for the
clang stackframe setup.

Link: https://github.com/ClangBuiltLinux/linux/issues/35

Cc: clang-built-linux@googlegroups.com
Suggested-by: Tri Vo <trong@google.com>
Signed-off-by: Nathan Huckleberry <nhuck@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

1 files changed, 7 insertions, 1 deletions

diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index b25c54585048..6d2ba454f25b 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -5,7 +5,7 @@
 # Copyright (C) 1995-2000 Russell King
 #
 
-lib-y           := backtrace.o changebit.o csumipv6.o csumpartial.o   \
+lib-y           := changebit.o csumipv6.o csumpartial.o               \
                    csumpartialcopy.o csumpartialcopyuser.o clearbit.o \
                    delay.o delay-loop.o findbit.o memchr.o memcpy.o   \
                    memmove.o memset.o setbit.o                        \
@@ -19,6 +19,12 @@ lib-y		:= backtrace.o changebit.o csumipv6.o csumpartial.o   \
 mmu-y           := clear_user.o copy_page.o getuser.o putuser.o       \
                    copy_from_user.o copy_to_user.o
 
+ifdef CONFIG_CC_IS_CLANG
+  lib-y += backtrace-clang.o
+else
+  lib-y += backtrace.o
+endif
+
 # using lib_ here won't override already available weak symbols
 obj-$(CONFIG_UACCESS_WITH_MEMCPY) += uaccess_with_memcpy.o