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Date:   Mon, 28 Oct 2019 08:57:21 -0700
Message-Id: <20191028155722.23419-1-ndesaulniers@google.com>
Mime-Version: 1.0
Subject: [PATCH] hexagon: work around compiler crash
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     bcain@codeaurora.org
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Sid Manning <sidneym@quicinc.com>,
        Allison Randal <allison@lohutok.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Richard Fontana <rfontana@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org,
        clang-built-linux@googlegroups.com
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Sender: linux-kernel-owner@vger.kernel.org
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Clang cannot translate the string "r30" into a valid register yet.

Link: https://github.com/ClangBuiltLinux/linux/issues/755
Suggested-by: Sid Manning <sidneym@quicinc.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
 arch/hexagon/kernel/stacktrace.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/hexagon/kernel/stacktrace.c b/arch/hexagon/kernel/stacktrace.c
index 35f29423fda8..5ed02f699479 100644
--- a/arch/hexagon/kernel/stacktrace.c
+++ b/arch/hexagon/kernel/stacktrace.c
@@ -11,8 +11,6 @@
 #include <linux/thread_info.h>
 #include <linux/module.h>
 
-register unsigned long current_frame_pointer asm("r30");
-
 struct stackframe {
 	unsigned long fp;
 	unsigned long rets;
@@ -30,7 +28,7 @@ void save_stack_trace(struct stack_trace *trace)
 
 	low = (unsigned long)task_stack_page(current);
 	high = low + THREAD_SIZE;
-	fp = current_frame_pointer;
+	fp = (unsigned long)__builtin_frame_address(0);
 
 	while (fp >= low && fp <= (high - sizeof(*frame))) {
 		frame = (struct stackframe *)fp;
-- 
2.24.0.rc0.303.g954a862665-goog