When gcc atomic intrinsics are not available (such as on RHEL 5 with gcc 4.1.2), we were getting link errors due to multiple definitions: ./.libs/libvirt_util.a(libvirt_util_la-virobject.o): In function `virAtomicIntXor': /home/dummy/l,ibvirt/src/util/viratomoic.h:404: multiple definition of `virAtomicIntXor' ./.libs/libvirt_util.a(libvirt_util_la-viratomic.o):/home/dummy/libvirt/src/util/viratomic.h:404: first defined here Solve this by conditionally marking the functions static (the condition avoids falling foul of gcc warnings about unused static function declarations). * src/util/viratomic.h: When not using gcc intrinsics, use static functions to avoid linker errors on duplicate functions. --- Pushing under the build-breaker rule. Tested on both RHEL 5 and modern gcc of F17. Oh, and I just noticed my indentation is off, while preparing this email; I'll squash in the whitespace fix before pushing. src/util/viratomic.h | 75 ++++++++++++++++++++++++++++------------------------ 1 file changed, 41 insertions(+), 34 deletions(-) diff --git a/src/util/viratomic.h b/src/util/viratomic.h index fa0a89a..95c7f5c 100644 --- a/src/util/viratomic.h +++ b/src/util/viratomic.h @@ -28,6 +28,12 @@ # include "internal.h" +# ifdef VIR_ATOMIC_OPS_GCC +# define VIR_STATIC /* Nothing; we just never define the functions */ +# else +# define VIR_STATIC static +# endif + /** * virAtomicIntGet: * Gets the current value of atomic. @@ -35,7 +41,7 @@ * This call acts as a full compiler and hardware memory barrier * (before the get) */ -int virAtomicIntGet(volatile int *atomic) +VIR_STATIC int virAtomicIntGet(volatile int *atomic) ATTRIBUTE_NONNULL(1); /** @@ -45,8 +51,8 @@ int virAtomicIntGet(volatile int *atomic) * This call acts as a full compiler and hardware memory barrier * (after the set) */ -void virAtomicIntSet(volatile int *atomic, - int newval) +VIR_STATIC void virAtomicIntSet(volatile int *atomic, + int newval) ATTRIBUTE_NONNULL(1); /** @@ -58,7 +64,7 @@ void virAtomicIntSet(volatile int *atomic, * * This call acts as a full compiler and hardware memory barrier. */ -int virAtomicIntInc(volatile int *atomic) +VIR_STATIC int virAtomicIntInc(volatile int *atomic) ATTRIBUTE_NONNULL(1); /** @@ -70,7 +76,7 @@ int virAtomicIntInc(volatile int *atomic) * * This call acts as a full compiler and hardware memory barrier. */ -bool virAtomicIntDecAndTest(volatile int *atomic) +VIR_STATIC bool virAtomicIntDecAndTest(volatile int *atomic) ATTRIBUTE_NONNULL(1); /** @@ -86,9 +92,9 @@ bool virAtomicIntDecAndTest(volatile int *atomic) * * This call acts as a full compiler and hardware memory barrier. */ -bool virAtomicIntCompareExchange(volatile int *atomic, - int oldval, - int newval) +VIR_STATIC bool virAtomicIntCompareExchange(volatile int *atomic, + int oldval, + int newval) ATTRIBUTE_NONNULL(1); /** @@ -100,8 +106,8 @@ bool virAtomicIntCompareExchange(volatile int *atomic, * * This call acts as a full compiler and hardware memory barrier. */ -int virAtomicIntAdd(volatile int *atomic, - int val) +VIR_STATIC int virAtomicIntAdd(volatile int *atomic, + int val) ATTRIBUTE_NONNULL(1); /** @@ -114,8 +120,8 @@ int virAtomicIntAdd(volatile int *atomic, * Think of this operation as an atomic version of * { tmp = *atomic; *atomic &= val; return tmp; } */ -unsigned int virAtomicIntAnd(volatile unsigned int *atomic, - unsigned int val) +VIR_STATIC unsigned int virAtomicIntAnd(volatile unsigned int *atomic, + unsigned int val) ATTRIBUTE_NONNULL(1); /** @@ -128,8 +134,8 @@ unsigned int virAtomicIntAnd(volatile unsigned int *atomic, * * This call acts as a full compiler and hardware memory barrier. */ -unsigned int virAtomicIntOr(volatile unsigned int *atomic, - unsigned int val) +VIR_STATIC unsigned int virAtomicIntOr(volatile unsigned int *atomic, + unsigned int val) ATTRIBUTE_NONNULL(1); /** @@ -142,10 +148,11 @@ unsigned int virAtomicIntOr(volatile unsigned int *atomic, * * This call acts as a full compiler and hardware memory barrier. */ -unsigned int virAtomicIntXor(volatile unsigned int *atomic, - unsigned int val) +VIR_STATIC unsigned int virAtomicIntXor(volatile unsigned int *atomic, + unsigned int val) ATTRIBUTE_NONNULL(1); +# undef VIR_STATIC # ifdef VIR_ATOMIC_OPS_GCC @@ -224,14 +231,14 @@ unsigned int virAtomicIntXor(volatile unsigned int *atomic, /* * http://msdn.microsoft.com/en-us/library/ms684122(v=vs.85).aspx */ -inline int +static inline int virAtomicIntGet(volatile int *atomic) { MemoryBarrier(); return *atomic; } -inline void +static inline void virAtomicIntSet(volatile int *atomic, int newval) { @@ -239,19 +246,19 @@ virAtomicIntSet(volatile int *atomic, MemoryBarrier(); } -inline int +static inline int virAtomicIntInc(volatile int *atomic) { return InterlockedIncrement((volatile LONG *)atomic); } -inline bool +static inline bool virAtomicIntDecAndTest(volatile int *atomic) { return InterlockedDecrement((volatile LONG *)atomic) == 0; } -inline bool +static inline bool virAtomicIntCompareExchange(volatile int *atomic, int oldval, int newval) @@ -259,28 +266,28 @@ virAtomicIntCompareExchange(volatile int *atomic, return InterlockedCompareExchange((volatile LONG *)atomic, newval, oldval) == oldval; } -inline int +static inline int virAtomicIntAdd(volatile int *atomic, int val) { return InterlockedExchangeAdd((volatile LONG *)atomic, val); } -inline unsigned int +static inline unsigned int virAtomicIntAnd(volatile unsigned int *atomic, unsigned int val) { return InterlockedAnd((volatile LONG *)atomic, val); } -inline unsigned int +static inline unsigned int virAtomicIntOr(volatile unsigned int *atomic, unsigned int val) { return InterlockedOr((volatile LONG *)atomic, val); } -inline unsigned int +static inline unsigned int virAtomicIntXor(volatile unsigned int *atomic, unsigned int val) { @@ -294,7 +301,7 @@ virAtomicIntXor(volatile unsigned int *atomic, extern pthread_mutex_t virAtomicLock; -inline int +static inline int virAtomicIntGet(volatile int *atomic) { int value; @@ -306,7 +313,7 @@ virAtomicIntGet(volatile int *atomic) return value; } -inline void +static inline void virAtomicIntSet(volatile int *atomic, int value) { @@ -315,7 +322,7 @@ virAtomicIntSet(volatile int *atomic, pthread_mutex_unlock(&virAtomicLock); } -inline int +static inline int virAtomicIntInc(volatile int *atomic) { int value; @@ -327,7 +334,7 @@ virAtomicIntInc(volatile int *atomic) return value; } -inline bool +static inline bool virAtomicIntDecAndTest(volatile int *atomic) { bool is_zero; @@ -339,7 +346,7 @@ virAtomicIntDecAndTest(volatile int *atomic) return is_zero; } -inline bool +static inline bool virAtomicIntCompareExchange(volatile int *atomic, int oldval, int newval) @@ -356,7 +363,7 @@ virAtomicIntCompareExchange(volatile int *atomic, return success; } -inline int +static inline int virAtomicIntAdd(volatile int *atomic, int val) { @@ -370,7 +377,7 @@ virAtomicIntAdd(volatile int *atomic, return oldval; } -inline unsigned int +static inline unsigned int virAtomicIntAnd(volatile unsigned int *atomic, unsigned int val) { @@ -384,7 +391,7 @@ virAtomicIntAnd(volatile unsigned int *atomic, return oldval; } -inline unsigned int +static inline unsigned int virAtomicIntOr(volatile unsigned int *atomic, unsigned int val) { @@ -398,7 +405,7 @@ virAtomicIntOr(volatile unsigned int *atomic, return oldval; } -inline unsigned int +static inline unsigned int virAtomicIntXor(volatile unsigned int *atomic, unsigned int val) { -- 1.7.11.4