--- a/config/rules.mk
+++ b/config/rules.mk
@@ -343,25 +343,17 @@ endif
 
 ifdef MAPFILE
 OS_LDFLAGS += -MAP:$(MAPFILE)
 endif
 
 endif # !GNU_CC
 
 ifdef ENABLE_CXX_EXCEPTIONS
-ifdef GNU_CC
-CXXFLAGS		+= -fexceptions
-else
-ifeq (,$(filter-out 1200 1300 1310,$(_MSC_VER)))
-CXXFLAGS		+= -GX
-else
-CXXFLAGS		+= -EHsc
-endif # _MSC_VER
-endif # GNU_CC
+CXXFLAGS += $(MOZ_EXCEPTIONS_FLAGS_ON) -DMOZ_CPP_EXCEPTIONS=1
 endif # ENABLE_CXX_EXCEPTIONS
 endif # WINNT
 
 ifeq ($(SOLARIS_SUNPRO_CXX),1)
 CXXFLAGS += -features=extensions -D__FUNCTION__=__func__
 ifeq (86,$(findstring 86,$(OS_TEST)))
 OS_LDFLAGS += -M $(topsrcdir)/config/solaris_ia32.map
 endif # x86

--- a/configure.in
+++ b/configure.in
@@ -2641,16 +2641,18 @@ alpha*-*-osf*)
     MOZ_MEMORY=1
     if test "$SOLARIS_SUNPRO_CC"; then
        LIBS="-lCrun -lCstd $LIBS"
        NS_USE_NATIVE=1
        MOZ_FIX_LINK_PATHS=
        AC_DEFINE(NSCAP_DISABLE_DEBUG_PTR_TYPES)
        CFLAGS="$CFLAGS -xlibmieee -xstrconst -xbuiltin=%all"
        CXXFLAGS="$CXXFLAGS -xlibmieee -xbuiltin=%all -features=tmplife,tmplrefstatic -norunpath"
+       _MOZ_EXCEPTIONS_FLAGS_ON='-features=except'
+       _MOZ_EXCEPTIONS_FLAGS_OFF='-features=no%except'
        LDFLAGS="-xildoff -z lazyload -z combreloc $LDFLAGS"
        if test -z "$CROSS_COMPILE" && test -f /usr/lib/ld/map.noexstk; then
            _SAVE_LDFLAGS=$LDFLAGS
            LDFLAGS="-M /usr/lib/ld/map.noexstk $LDFLAGS" 
            AC_TRY_LINK([#include <stdio.h>],
                        [printf("Hello World\n");],
                        ,
                        [LDFLAGS=$_SAVE_LDFLAGS])
@@ -7517,26 +7519,27 @@ if test "$_MOZ_USE_RTTI"; then
    _MOZ_RTTI_FLAGS=$_MOZ_RTTI_FLAGS_ON
 else
    _MOZ_RTTI_FLAGS=$_MOZ_RTTI_FLAGS_OFF
 fi
 
 AC_SUBST(_MOZ_RTTI_FLAGS_ON)
 
 dnl ========================================================
-dnl C++ exceptions (g++/egcs only - for now)
+dnl C++ exceptions (g++/VC/irix6/Sun only - for now)
 dnl Should be smarter and check that the compiler does indeed have exceptions
 dnl ========================================================
 MOZ_ARG_ENABLE_BOOL(cpp-exceptions,
 [  --enable-cpp-exceptions Enable C++ exceptions ],
 [ _MOZ_CPP_EXCEPTIONS=1 ],
 [ _MOZ_CPP_EXCEPTIONS= ])
 
 if test "$_MOZ_CPP_EXCEPTIONS"; then
     _MOZ_EXCEPTIONS_FLAGS=$_MOZ_EXCEPTIONS_FLAGS_ON
+    AC_DEFINE(MOZ_CPP_EXCEPTIONS)
 else
     _MOZ_EXCEPTIONS_FLAGS=$_MOZ_EXCEPTIONS_FLAGS_OFF
 fi
 
 AC_SUBST(_MOZ_EXCEPTIONS_FLAGS_ON)
 
 # Irix & OSF native compilers do not like exception declarations 
 # when exceptions are disabled

--- a/js/src/config/rules.mk
+++ b/js/src/config/rules.mk
@@ -343,25 +343,17 @@ endif
 
 ifdef MAPFILE
 OS_LDFLAGS += -MAP:$(MAPFILE)
 endif
 
 endif # !GNU_CC
 
 ifdef ENABLE_CXX_EXCEPTIONS
-ifdef GNU_CC
-CXXFLAGS		+= -fexceptions
-else
-ifeq (,$(filter-out 1200 1300 1310,$(_MSC_VER)))
-CXXFLAGS		+= -GX
-else
-CXXFLAGS		+= -EHsc
-endif # _MSC_VER
-endif # GNU_CC
+CXXFLAGS += $(MOZ_EXCEPTIONS_FLAGS_ON) -DMOZ_CPP_EXCEPTIONS=1
 endif # ENABLE_CXX_EXCEPTIONS
 endif # WINNT
 
 ifeq ($(SOLARIS_SUNPRO_CXX),1)
 CXXFLAGS += -features=extensions -D__FUNCTION__=__func__
 ifeq (86,$(findstring 86,$(OS_TEST)))
 OS_LDFLAGS += -M $(topsrcdir)/config/solaris_ia32.map
 endif # x86

--- a/js/src/configure.in
+++ b/js/src/configure.in
@@ -2393,16 +2393,18 @@ alpha*-*-osf*)
     LDFLAGS="$LDFLAGS -z ignore -R '\$\$ORIGIN:\$\$ORIGIN/..'"
     if test "$SOLARIS_SUNPRO_CC"; then
        LIBS="-lCrun -lCstd $LIBS"
        NS_USE_NATIVE=1
        MOZ_FIX_LINK_PATHS=
        AC_DEFINE(NSCAP_DISABLE_DEBUG_PTR_TYPES)
        CFLAGS="$CFLAGS -xlibmieee -xstrconst -xbuiltin=%all"
        CXXFLAGS="$CXXFLAGS -xlibmieee -xbuiltin=%all -features=tmplife,tmplrefstatic -norunpath"
+       _MOZ_EXCEPTIONS_FLAGS_ON='-features=except'
+       _MOZ_EXCEPTIONS_FLAGS_OFF='-features=no%except'
        LDFLAGS="-xildoff -z lazyload -z combreloc $LDFLAGS"
        if test -z "$CROSS_COMPILE" && test -f /usr/lib/ld/map.noexstk; then
            _SAVE_LDFLAGS=$LDFLAGS
            LDFLAGS="-M /usr/lib/ld/map.noexstk $LDFLAGS" 
            AC_TRY_LINK([#include <stdio.h>],
                        [printf("Hello World\n");],
                        ,
                        [LDFLAGS=$_SAVE_LDFLAGS])
@@ -4775,26 +4777,27 @@ if test "$_MOZ_USE_RTTI"; then
    _MOZ_RTTI_FLAGS=$_MOZ_RTTI_FLAGS_ON
 else
    _MOZ_RTTI_FLAGS=$_MOZ_RTTI_FLAGS_OFF
 fi
 
 AC_SUBST(_MOZ_RTTI_FLAGS_ON)
 
 dnl ========================================================
-dnl C++ exceptions (g++/egcs only - for now)
+dnl C++ exceptions (g++/VC/irix6/Sun only - for now)
 dnl Should be smarter and check that the compiler does indeed have exceptions
 dnl ========================================================
 MOZ_ARG_ENABLE_BOOL(cpp-exceptions,
 [  --enable-cpp-exceptions Enable C++ exceptions ],
 [ _MOZ_CPP_EXCEPTIONS=1 ],
 [ _MOZ_CPP_EXCEPTIONS= ])
 
 if test "$_MOZ_CPP_EXCEPTIONS"; then
     _MOZ_EXCEPTIONS_FLAGS=$_MOZ_EXCEPTIONS_FLAGS_ON
+    AC_DEFINE(MOZ_CPP_EXCEPTIONS)
 else
     _MOZ_EXCEPTIONS_FLAGS=$_MOZ_EXCEPTIONS_FLAGS_OFF
 fi
 
 AC_SUBST(_MOZ_EXCEPTIONS_FLAGS_ON)
 
 # Irix & OSF native compilers do not like exception declarations 
 # when exceptions are disabled

--- a/memory/mozalloc/mozalloc.h
+++ b/memory/mozalloc/mozalloc.h
@@ -68,16 +68,23 @@
 #if defined(NS_ALWAYS_INLINE)
 #  define MOZALLOC_INLINE NS_ALWAYS_INLINE inline
 #elif defined(HAVE_FORCEINLINE)
 #  define MOZALLOC_INLINE __forceinline
 #else
 #  define MOZALLOC_INLINE inline
 #endif
 
+/* Workaround build problem with Sun Studio 12 */
+#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
+#  undef NS_WARN_UNUSED_RESULT
+#  define NS_WARN_UNUSED_RESULT
+#  undef NS_ATTR_MALLOC
+#  define NS_ATTR_MALLOC
+#endif
 
 #if defined(__cplusplus)
 extern "C" {
 #endif /* ifdef __cplusplus */
 
 
 /* 
  * If we don't have these system functions, but do have jemalloc
@@ -205,17 +212,17 @@ MOZALLOC_EXPORT void* moz_valloc(size_t 
  * visibility on OS X/gcc. These symbols are force-inline and not
  * exported. */
 #if defined(XP_MACOSX)
 #  define MOZALLOC_EXPORT_NEW MOZALLOC_EXPORT
 #else
 #  define MOZALLOC_EXPORT_NEW
 #endif
 
-#ifdef __MINGW32__
+#ifdef MOZ_CPP_EXCEPTIONS
 #define MOZALLOC_THROW_BAD_ALLOC throw(std::bad_alloc)
 #else
 #define MOZALLOC_THROW_BAD_ALLOC throw()
 #endif
 
 MOZALLOC_EXPORT_NEW MOZALLOC_INLINE
 void* operator new(size_t size) MOZALLOC_THROW_BAD_ALLOC
 {

--- a/toolkit/components/ctypes/tests/Makefile.in
+++ b/toolkit/components/ctypes/tests/Makefile.in
@@ -52,17 +52,17 @@ NO_DIST_INSTALL = 1
 CPPSRCS = jsctypes-test.cpp
 
 LOCAL_INCLUDES = \
     -I$(topsrcdir)/js/src/ctypes \
     $(NULL)
 
 EXTRA_DSO_LDOPTS += \
     $(XPCOM_STANDALONE_GLUE_LDOPTS) \
-    $(MOZALLOC_LIB) \
+    -L$(LIBXUL_DIST)/lib $(MOZALLOC_LIB) \
     $(NSPR_LIBS) \
     $(NULL)
 
 XPCSHELL_TESTS = unit
 
 include $(topsrcdir)/config/rules.mk
 
 xpctestdir = $(testxpcobjdir)/$(MODULE)/unit

--- a/xpcom/build/Makefile.in
+++ b/xpcom/build/Makefile.in
@@ -145,17 +145,17 @@ include $(topsrcdir)/config/rules.mk
 
 DEFINES		+= \
 		-D_IMPL_NS_COM \
 		-D_IMPL_NS_STRINGAPI \
 		-DEXPORT_XPT_API \
 		-DEXPORT_XPTC_API
 
 EXTRA_DSO_LDOPTS +=				\
-	$(MOZALLOC_LIB)				\
+	-L$(LIBXUL_DIST)/lib $(MOZALLOC_LIB)    \
 	$(NSPR_LIBS)				\
 	$(NULL)
 
 ifdef TARGET_XPCOM_ABI
 DEFINES += -DTARGET_XPCOM_ABI=\"$(TARGET_XPCOM_ABI)\"
 endif
 
 ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))