X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=urcu%2Fcompiler.h;h=074e70026a056cab15d1b05b7537ac333c2daedf;hb=b52a3dc23521f7a21fb5ab3d2b53dad89c586ee4;hp=974885a73f36c08e322bb6606bb3cd0e8e964ddd;hpb=bdffa73aa208ad5f1e5b3a3cb6cbf86ac6996559;p=userspace-rcu.git

diff --git a/urcu/compiler.h b/urcu/compiler.h
index 974885a..074e700 100644
--- a/urcu/compiler.h
+++ b/urcu/compiler.h
@@ -24,7 +24,7 @@
 #define caa_likely(x)	__builtin_expect(!!(x), 1)
 #define caa_unlikely(x)	__builtin_expect(!!(x), 0)
 
-#define	cmm_barrier()	asm volatile("" : : : "memory")
+#define	cmm_barrier()	__asm__ __volatile__ ("" : : : "memory")
 
 /*
  * Instruct the compiler to perform only a single access to a variable
@@ -38,7 +38,7 @@
  * use is to mediate communication between process-level code and irq/NMI
  * handlers, all running on the same CPU.
  */
-#define CMM_ACCESS_ONCE(x)	(*(volatile __typeof__(x) *)&(x))
+#define CMM_ACCESS_ONCE(x)	(*(__volatile__  __typeof__(x) *)&(x))
 
 #ifndef caa_max
 #define caa_max(a,b) ((a)>(b)?(a):(b))
@@ -70,7 +70,7 @@
 	})
 
 #define CAA_BUILD_BUG_ON_ZERO(cond) (sizeof(struct { int:-!!(cond); }))
-#define CAA_BUILD_BUG_ON(cond) ((void)BUILD_BUG_ON_ZERO(cond))
+#define CAA_BUILD_BUG_ON(cond) ((void)CAA_BUILD_BUG_ON_ZERO(cond))
 
 /*
  * __rcu is an annotation that documents RCU pointer accesses that need
@@ -86,9 +86,33 @@
 #define URCU_FORCE_CAST(type, arg)	((type) (arg))
 #endif
 
-#define caa_is_signed_type(type)	(((type) (-1)) < 0)
+#define caa_is_signed_type(type)	((type) -1 < (type) 0)
 
-#define caa_cast_long_keep_sign(v)	\
-	(caa_is_signed_type(__typeof__(v)) ? (long) (v) : (unsigned long) (v))
+/*
+ * Sign-extend to long if needed, and output type is unsigned long.
+ */
+#define caa_cast_long_keep_sign(v)		\
+	(caa_is_signed_type(__typeof__(v)) ?	\
+		(unsigned long) (long) (v) :	\
+		(unsigned long) (v))
+
+/*
+ * Don't allow compiling with buggy compiler.
+ */
+
+#ifdef __GNUC__
+# define URCU_GCC_VERSION	(__GNUC__ * 10000 \
+				+ __GNUC_MINOR__ * 100 \
+				+ __GNUC_PATCHLEVEL__)
+
+/*
+ * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854
+ */
+# ifdef __ARMEL__
+#  if URCU_GCC_VERSION >= 40800 && URCU_GCC_VERSION <= 40802
+#   error Your gcc version produces clobbered frame accesses
+#  endif
+# endif
+#endif
 
 #endif /* _URCU_COMPILER_H */