Reland: Introduce a V8_NORETURN macro and use it to make GCC 4.9.2 happy again.

include/v8config.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8CONFIG_H_
 #define V8CONFIG_H_
 
 // clang-format off
 
 // Platform headers for feature detection below.
@@ skipping 156 matching lines @@
 //
 // Compiler-specific feature detection
 //
 //  V8_HAS___ALIGNOF                    - __alignof(type) operator supported
 //  V8_HAS___ALIGNOF__                  - __alignof__(type) operator supported
 //  V8_HAS_ATTRIBUTE_ALIGNED            - __attribute__((aligned(n))) supported
 //  V8_HAS_ATTRIBUTE_ALWAYS_INLINE      - __attribute__((always_inline))
 //                                        supported
 //  V8_HAS_ATTRIBUTE_DEPRECATED         - __attribute__((deprecated)) supported
 //  V8_HAS_ATTRIBUTE_NOINLINE           - __attribute__((noinline)) supported
+//  V8_HAS_ATTRIBUTE_NORETURN           - __attribute__((noreturn)) 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
 //  V8_HAS_BUILTIN_CLZ                  - __builtin_clz() supported
 //  V8_HAS_BUILTIN_CTZ                  - __builtin_ctz() supported
 //  V8_HAS_BUILTIN_EXPECT               - __builtin_expect() supported
 //  V8_HAS_BUILTIN_FRAME_ADDRESS        - __builtin_frame_address() supported
 //  V8_HAS_BUILTIN_POPCOUNT             - __builtin_popcount() supported
 //  V8_HAS_BUILTIN_SADD_OVERFLOW        - __builtin_sadd_overflow() supported
 //  V8_HAS_BUILTIN_SSUB_OVERFLOW        - __builtin_ssub_overflow() supported
 //  V8_HAS_BUILTIN_UADD_OVERFLOW        - __builtin_uadd_overflow() supported
 //  V8_HAS_DECLSPEC_ALIGN               - __declspec(align(n)) supported
 //  V8_HAS_DECLSPEC_DEPRECATED          - __declspec(deprecated) supported
 //  V8_HAS_DECLSPEC_NOINLINE            - __declspec(noinline) supported
 //  V8_HAS_DECLSPEC_SELECTANY           - __declspec(selectany) supported
+//  V8_HAS_DECLSPEC_NORETURN            - __declspec(noreturn) supported
 //  V8_HAS___FORCEINLINE                - __forceinline supported
 //
 // Note that testing for compilers and/or features must be done using #if
 // not #ifdef. For example, to test for Intel C++ Compiler, use:
 //  #if V8_CC_INTEL
 //   ...
 //  #endif
 
 #if defined(__clang__)
 
 #if defined(__GNUC__)  // Clang in gcc mode.
 # define V8_CC_GNU 1
 #endif
 
 // Clang defines __alignof__ as alias for __alignof
 # define V8_HAS___ALIGNOF 1
 # define V8_HAS___ALIGNOF__ V8_HAS___ALIGNOF
 
 # define V8_HAS_ATTRIBUTE_ALIGNED (__has_attribute(aligned))
 # 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_NORETURN (__has_attribute(noreturn))
 # 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))
 
 # define V8_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz))
 # define V8_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz))
 # define V8_HAS_BUILTIN_EXPECT (__has_builtin(__builtin_expect))
 # define V8_HAS_BUILTIN_FRAME_ADDRESS (__has_builtin(__builtin_frame_address))
 # define V8_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount))
@@ skipping 21 matching lines @@
 # define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0))
 
 # define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0))
 // always_inline is available in gcc 4.0 but not very reliable until 4.4.
 // Works around "sorry, unimplemented: inlining failed" build errors with
 // older compilers.
 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0))
 # 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_NORETURN (V8_GNUC_PREREQ(2, 5, 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))
 
 # define V8_HAS_BUILTIN_CLZ (V8_GNUC_PREREQ(3, 4, 0))
 # define V8_HAS_BUILTIN_CTZ (V8_GNUC_PREREQ(3, 4, 0))
 # define V8_HAS_BUILTIN_EXPECT (V8_GNUC_PREREQ(2, 96, 0))
 # define V8_HAS_BUILTIN_FRAME_ADDRESS (V8_GNUC_PREREQ(2, 96, 0))
 # define V8_HAS_BUILTIN_POPCOUNT (V8_GNUC_PREREQ(3, 4, 0))
@@ skipping 12 matching lines @@
 #endif
 
 #if defined(_MSC_VER)
 # define V8_CC_MSVC 1
 # define V8_HAS___ALIGNOF 1
 
 # define V8_HAS_DECLSPEC_ALIGN 1
 # define V8_HAS_DECLSPEC_DEPRECATED 1
 # define V8_HAS_DECLSPEC_NOINLINE 1
 # define V8_HAS_DECLSPEC_SELECTANY 1
+# define V8_HAS_DECLSPEC_NORETURN 1
 
 # define V8_HAS___FORCEINLINE 1
 
 #endif
 
 
 // -----------------------------------------------------------------------------
 // Helper macros
 
 // A macro used to make better inlining. Don't bother for debug builds.
@@ skipping 14 matching lines @@
 //   V8_NOINLINE int GetMinusOne() { return -1; }
 #if !defined(DEBUG) && V8_HAS_ATTRIBUTE_NOINLINE
 # define V8_NOINLINE __attribute__((noinline))
 #elif !defined(DEBUG) && V8_HAS_DECLSPEC_NOINLINE
 # define V8_NOINLINE __declspec(noinline)
 #else
 # define V8_NOINLINE /* NOT SUPPORTED */
 #endif
 
 
+// A macro used to tell the compiler that a particular function never returns.
+// Use like:
+//   V8_NORETURN void MyAbort() { abort(); }
+#if V8_HAS_ATTRIBUTE_NORETURN
+# define V8_NORETURN __attribute__((noreturn))
+#elif HAS_DECLSPEC_NORETURN
+# define V8_NORETURN __declspec(noreturn)
+#else
+# define V8_NORETURN /* NOT SUPPORTED */
+#endif
+
+
 // A macro (V8_DEPRECATED) to mark classes or functions as deprecated.
 #if defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED_MESSAGE
 #define V8_DEPRECATED(message, declarator) \
   declarator __attribute__((deprecated(message)))
 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_ATTRIBUTE_DEPRECATED
 #define V8_DEPRECATED(message, declarator) \
   declarator __attribute__((deprecated))
 #elif defined(V8_DEPRECATION_WARNINGS) && V8_HAS_DECLSPEC_DEPRECATED
 #define V8_DEPRECATED(message, declarator) __declspec(deprecated) declarator
 #else
@@ skipping 83 matching lines @@
 //   int foo() WARN_UNUSED_RESULT;
 #if V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT
 #define V8_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
 #else
 #define V8_WARN_UNUSED_RESULT /* NOT SUPPORTED */
 #endif
 
 // clang-format on
 
 #endif  // V8CONFIG_H_