diff -up oiio-Release-1.1.3/src/include/thread.h.ppc oiio-Release-1.1.3/src/include/thread.h
--- oiio-Release-1.1.3/src/include/thread.h.ppc	2013-01-10 02:13:37.000000000 +0100
+++ oiio-Release-1.1.3/src/include/thread.h	2013-01-28 15:07:23.190624263 +0100
@@ -98,7 +98,7 @@
 #endif
 
 #if defined(__GNUC__) && (defined(_GLIBCXX_ATOMIC_BUILTINS) || (__GNUC__ * 100 + __GNUC_MINOR__ >= 401))
-#if !defined(__FreeBSD__) || defined(__x86_64__)
+#if !defined(__FreeBSD__) && !defined(__PPC__) || defined(__x86_64__)
 #define USE_GCC_ATOMICS
 #endif
 #endif
@@ -224,6 +224,11 @@ atomic_exchange_and_add (volatile int *a
 #elif defined(_MSC_VER)
     // Windows
     return _InterlockedExchangeAdd ((volatile LONG *)at, x);
+#elif defined (__PPC__)
+    long long r;
+    r = *at;
+    *at += x;
+    return r;
 #else
 #   error No atomics on this platform.
 #endif
@@ -249,6 +254,11 @@ atomic_exchange_and_add (volatile long l
 #  else
     return InterlockedExchangeAdd64 ((volatile LONGLONG *)at, x);
 #  endif
+#elif defined (__PPC__)
+   long long r;
+   r = *at;
+   *at += x;
+   return r;
 #else
 #   error No atomics on this platform.
 #endif
@@ -274,6 +284,8 @@ atomic_compare_and_exchange (volatile in
     return OSAtomicCompareAndSwap32Barrier (compareval, newval, at);
 #elif defined(_MSC_VER)
     return (_InterlockedCompareExchange ((volatile LONG *)at, newval, compareval) == compareval);
+#elif defined(__PPC__)
+    return ((*at == compareval) ? (*at = newval), 1 : 0);
 #else
 #   error No atomics on this platform.
 #endif
@@ -293,6 +305,8 @@ atomic_compare_and_exchange (volatile lo
     return OSAtomicCompareAndSwap64Barrier (compareval, newval, at);
 #elif defined(_MSC_VER)
     return (_InterlockedCompareExchange64 ((volatile LONGLONG *)at, newval, compareval) == compareval);
+#elif defined(__PPC__)
+    return ((*at == compareval) ? (*at = newval), 1 : 0);
 #else
 #   error No atomics on this platform.
 #endif
@@ -324,7 +338,7 @@ pause (int delay)
 {
 #if USE_TBB
     __TBB_Pause(delay);
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) && !defined (__PPC__)
     for (int i = 0; i < delay; ++i) {
         __asm__ __volatile__("pause;");
     }