Fix compilation with GCC 4.8

BUG=v8:2767,v8:2149
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/69413002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17641 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

include/v8.h

@@ -5821,7 +5821,6 @@ void ReturnValue<T>::Set(int32_t i) {
 template<typename T>
 void ReturnValue<T>::Set(uint32_t i) {
   TYPE_CHECK(T, Integer);
-  typedef internal::Internals I;
   // Can't simply use INT32_MAX here for whatever reason.
   bool fits_into_int32_t = (i & (1U << 31)) == 0;
   if (V8_LIKELY(fits_into_int32_t)) {

include/v8config.h

@@ -187,6 +187,7 @@
 //                                        supported
 //  V8_HAS_ATTRIBUTE_DEPRECATED         - __attribute__((deprecated)) supported
 //  V8_HAS_ATTRIBUTE_NOINLINE           - __attribute__((noinline)) supported
+//  V8_HAS_ATTRIBUTE_UNUSED             - __attribute__((unused)) supported
 //  V8_HAS_ATTRIBUTE_VISIBILITY         - __attribute__((visibility)) supported
 //  V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT - __attribute__((warn_unused_result))
 //                                        supported
@@ -216,6 +217,7 @@
 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (__has_attribute(always_inline))
 # define V8_HAS_ATTRIBUTE_DEPRECATED (__has_attribute(deprecated))
 # define V8_HAS_ATTRIBUTE_NOINLINE (__has_attribute(noinline))
+# define V8_HAS_ATTRIBUTE_UNUSED (__has_attribute(unused))
 # define V8_HAS_ATTRIBUTE_VISIBILITY (__has_attribute(visibility))
 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
     (__has_attribute(warn_unused_result))
@@ -247,6 +249,7 @@
 # define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0))
 # define V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE (V8_GNUC_PREREQ(4, 5, 0))
 # define V8_HAS_ATTRIBUTE_NOINLINE (V8_GNUC_PREREQ(3, 4, 0))
+# define V8_HAS_ATTRIBUTE_UNUSED (V8_GNUC_PREREQ(2, 95, 0))
 # define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0))
 # define V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT \
     (!V8_CC_INTEL && V8_GNUC_PREREQ(4, 1, 0))
@@ -334,6 +337,14 @@ declarator __attribute__((deprecated))
 #endif
 
 
+// A macro to mark variables or types as unused, avoiding compiler warnings.
+#if V8_HAS_ATTRIBUTE_UNUSED
+# define V8_UNUSED __attribute__((unused))
+#else
+# define V8_UNUSED
+#endif
+
+
 // Annotate a function indicating the caller must examine the return value.
 // Use like:
 //   int foo() V8_WARN_UNUSED_RESULT;

src/checks.h

@@ -268,7 +268,7 @@ template <int> class StaticAssertionHelper { };
 #define STATIC_CHECK(test)                                                    \
   typedef                                                                     \
     StaticAssertionHelper<sizeof(StaticAssertion<static_cast<bool>((test))>)> \
-    SEMI_STATIC_JOIN(__StaticAssertTypedef__, __LINE__)
+    SEMI_STATIC_JOIN(__StaticAssertTypedef__, __LINE__) V8_UNUSED
 #endif
 
 

test/cctest/test-macro-assembler-x64.cc

@@ -2327,8 +2327,8 @@ TEST(PositiveSmiTimesPowerOfTwoToInteger64) {
 
 TEST(OperandOffset) {
   i::V8::Initialize(NULL);
-  int data[256];
-  for (int i = 0; i < 256; i++) { data[i] = i * 0x01010101; }
+  uint32_t data[256];
+  for (uint32_t i = 0; i < 256; i++) { data[i] = i * 0x01010101; }
 
   // Allocate an executable page of memory.
   size_t actual_size;