From aad6cdbcff0f5411a09ac524637fea62652786a3 Mon Sep 17 00:00:00 2001
From: Romain Naour <romain.naour@gmail.com>
Date: Fri, 8 May 2020 18:39:45 +0200
Subject: [PATCH] mips: Do not include hi and lo in __SYSCALL_CLOBBERS for R6
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From [1]
"GCC 10 (PR 91233) won't silently allow registers that are not architecturally
available to be present in the clobber list anymore, resulting in build failure
for mips*r6 targets in form of:
...
.../sysdep.h:146:2: error: the register ‘lo’ cannot be clobbered in ‘asm’ for the current target
  146 |  __asm__ volatile (      \
      |  ^~~~~~~

This is because base R6 ISA doesn't define hi and lo registers w/o DSP extension.
This patch provides the alternative definitions of __SYSCALL_CLOBBERS for r6
targets that won't include those registers."

[1] https://sourceware.org/git/?p=glibc.git;a=commit;h=020b2a97bb15f807c0482f0faee2184ed05bcad8

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Waldemar Brodkorb <wbx@openadk.org>
---
 libc/sysdeps/linux/mips/bits/syscalls.h | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/libc/sysdeps/linux/mips/bits/syscalls.h b/libc/sysdeps/linux/mips/bits/syscalls.h
index b8f80597e..13728ac55 100644
--- a/libc/sysdeps/linux/mips/bits/syscalls.h
+++ b/libc/sysdeps/linux/mips/bits/syscalls.h
@@ -270,8 +270,13 @@
 	_sys_result;							\
 })
 
-#define __SYSCALL_CLOBBERS "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", \
-	"$14", "$15", "$24", "$25", "hi", "lo", "memory"
+#if __mips_isa_rev >= 6
+# define __SYSCALL_CLOBBERS "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", \
+	 "$14", "$15", "$24", "$25", "memory"
+#else
+# define __SYSCALL_CLOBBERS "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", \
+	 "$14", "$15", "$24", "$25", "hi", "lo", "memory"
+#endif
 
 #else /* N32 || N64 */
 
@@ -327,8 +332,13 @@
 	_sys_result;							\
 })
 
-#define __SYSCALL_CLOBBERS "$1", "$3", "$10", "$11", "$12", "$13", \
-	"$14", "$15", "$24", "$25", "hi", "lo", "memory"
+#if __mips_isa_rev >= 6
+# define __SYSCALL_CLOBBERS "$1", "$3", "$10", "$11", "$12", "$13", \
+	 "$14", "$15", "$24", "$25", "memory"
+#else
+# define __SYSCALL_CLOBBERS "$1", "$3", "$10", "$11", "$12", "$13", \
+	 "$14", "$15", "$24", "$25", "hi", "lo", "memory"
+#endif
 
 #endif
 
-- 
2.25.4