Eliminate 'missing exception specification' warning in gc_cpp.cc (Clang)

* gc_cpp.cc (GC_NEW_DELETE_NEED_THROW): Define new macro (if not defined
yet) for GCC v4.2+ (or clang).
* gc_cpp.cc: Include new (for std::bad_alloc) if
GC_NEW_DELETE_NEED_THROW.
* gc_cpp.cc (GC_DECL_NEW_THROW, GC_DECL_DELETE_THROW): New macros
(used to eliminate compiler "missing exception specification" warning
for 'new' and 'delete' operators).
* gc_cpp.cc (new, delete, new[], delete[]): Use
GC_DECL_NEW/DELETE_THROW to define 'throw' clause properly.

1 files changed, 20 insertions, 6 deletions

diff --git a/gc_cpp.cc b/gc_cpp.cc
index 86792b04..9f64b748 100644
--- a/gc_cpp.cc
+++ b/gc_cpp.cc
@@ -29,22 +29,36 @@ built-in "new" and "delete".
 
 #include "gc_cpp.h"
 
-void* operator new( size_t size ) {
+#if !defined(GC_NEW_DELETE_NEED_THROW) && defined(__GNUC__) \
+    && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2))
+# define GC_NEW_DELETE_NEED_THROW
+#endif
+
+#ifdef GC_NEW_DELETE_NEED_THROW
+# include <new> /* for std::bad_alloc */
+# define GC_DECL_NEW_THROW throw(std::bad_alloc)
+# define GC_DECL_DELETE_THROW throw()
+#else
+# define GC_DECL_NEW_THROW /* empty */
+# define GC_DECL_DELETE_THROW /* empty */
+#endif /* !GC_NEW_DELETE_NEED_THROW */
+
+void* operator new( size_t size ) GC_DECL_NEW_THROW {
   return GC_MALLOC_UNCOLLECTABLE(size);
 }
 
 #if !defined(__CYGWIN__)
-  void operator delete( void* obj ) {
+  void operator delete( void* obj ) GC_DECL_DELETE_THROW {
     GC_FREE(obj);
   }
 #endif /* !__CYGWIN__ */
 
 #ifdef GC_OPERATOR_NEW_ARRAY
-  void* operator new[]( size_t size ) {
+  void* operator new[]( size_t size ) GC_DECL_NEW_THROW {
     return GC_MALLOC_UNCOLLECTABLE(size);
   }
 
-  void operator delete[]( void* obj ) {
+  void operator delete[]( void* obj ) GC_DECL_DELETE_THROW {
     GC_FREE(obj);
   }
 #endif /* GC_OPERATOR_NEW_ARRAY */
@@ -53,7 +67,7 @@ void* operator new( size_t size ) {
 
   // This new operator is used by VC++ in case of Debug builds!
   void* operator new( size_t size, int /* nBlockUse */,
-                     const char * szFileName, int nLine )
+                     const char * szFileName, int nLine ) GC_DECL_NEW_THROW
   {
 #   ifndef GC_DEBUG
       return GC_malloc_uncollectable(size);
@@ -65,7 +79,7 @@ void* operator new( size_t size ) {
 # if _MSC_VER > 1020
     // This new operator is used by VC++ 7.0 and later in Debug builds.
     void* operator new[]( size_t size, int nBlockUse,
-                         const char* szFileName, int nLine )
+                         const char* szFileName, int nLine ) GC_DECL_NEW_THROW
     {
       return operator new(size, nBlockUse, szFileName, nLine);
     }