[PATCH] x86-64: Use different constraint for gcc < 4.1 in bitops.h
+m is really correct for a RMW instruction, but some older gccs
error out. I finally gave in and ifdefed it.
This fixes compilation errors with some compiler version.
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/include/asm-x86_64/bitops.h b/include/asm-x86_64/bitops.h
index 5b535ea..8da9609 100644
--- a/include/asm-x86_64/bitops.h
+++ b/include/asm-x86_64/bitops.h
@@ -7,7 +7,13 @@
#include <asm/alternative.h>
-#define ADDR (*(volatile long *) addr)
+#if __GNUC__ < 4 || __GNUC_MINOR__ < 1
+/* Technically wrong, but this avoids compilation errors on some gcc
+ versions. */
+#define ADDR "=m" (*(volatile long *) addr)
+#else
+#define ADDR "+m" (*(volatile long *) addr)
+#endif
/**
* set_bit - Atomically set a bit in memory
@@ -23,7 +29,7 @@
{
__asm__ __volatile__( LOCK_PREFIX
"btsl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr) : "memory");
}
@@ -40,7 +46,7 @@
{
__asm__ volatile(
"btsl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr) : "memory");
}
@@ -58,7 +64,7 @@
{
__asm__ __volatile__( LOCK_PREFIX
"btrl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr));
}
@@ -66,7 +72,7 @@
{
__asm__ __volatile__(
"btrl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr));
}
@@ -86,7 +92,7 @@
{
__asm__ __volatile__(
"btcl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr));
}
@@ -103,7 +109,7 @@
{
__asm__ __volatile__( LOCK_PREFIX
"btcl %1,%0"
- :"+m" (ADDR)
+ :ADDR
:"dIr" (nr));
}
@@ -121,7 +127,7 @@
__asm__ __volatile__( LOCK_PREFIX
"btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr) : "memory");
return oldbit;
}
@@ -141,7 +147,7 @@
__asm__(
"btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr));
return oldbit;
}
@@ -160,7 +166,7 @@
__asm__ __volatile__( LOCK_PREFIX
"btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr) : "memory");
return oldbit;
}
@@ -180,7 +186,7 @@
__asm__(
"btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr));
return oldbit;
}
@@ -192,7 +198,7 @@
__asm__ __volatile__(
"btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr) : "memory");
return oldbit;
}
@@ -211,7 +217,7 @@
__asm__ __volatile__( LOCK_PREFIX
"btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
+ :"=r" (oldbit),ADDR
:"dIr" (nr) : "memory");
return oldbit;
}
@@ -237,7 +243,7 @@
__asm__ __volatile__(
"btl %2,%1\n\tsbbl %0,%0"
:"=r" (oldbit)
- :"m" (ADDR),"dIr" (nr));
+ :"m" (*(volatile long *)addr),"dIr" (nr));
return oldbit;
}