Make the linking of C++ ABI related code for exceptions optional.

The default is to have it enabled.

Signed-off-by: Arun Sharma <address@hidden>

diff --git a/configure.in b/configure.in
index c2374c5..7f7aef8 100644
--- a/configure.in
+++ b/configure.in
@@ -116,6 +116,14 @@ AC_ARG_ENABLE(debug,
 [  --enable-debug          turn on debug support (slows down execution)],
 [enable_debug=yes], [])
 
+AC_ARG_ENABLE(cxx_exceptions,
+[  --enable-cxx-exceptions use libunwind to handle C++ exceptions],
+[enable_cxx_exceptions=$enableval], [enable_cxx_exceptions=yes])
+if test x$enable_cxx_exceptions = xyes; then
+  AC_MSG_NOTICE([Enabling C++ exception support])
+fi
+AM_CONDITIONAL([SUPPORT_CXX_EXCEPTIONS], [test x$enable_cxx_exceptions = xyes])
+
 LIBUNWIND___THREAD
 
 save_LDFLAGS="$LDFLAGS"
diff --git a/src/Makefile.am b/src/Makefile.am
index ae113f4..7de3026 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -61,6 +61,7 @@ libunwind_la_SOURCES_generic =						\
 	mi/Gget_fpreg.c mi/Gset_fpreg.c					\
 	mi/Gset_caching_policy.c
 
+if SUPPORT_CXX_EXCEPTIONS
 libunwind_la_SOURCES_local_unwind =					\
 	unwind/Backtrace.c unwind/DeleteException.c			\
 	unwind/FindEnclosingFunction.c unwind/ForcedUnwind.c		\
@@ -69,6 +70,7 @@ libunwind_la_SOURCES_local_unwind =					\
 	unwind/GetRegionStart.c unwind/GetTextRelBase.c			\
 	unwind/RaiseException.c unwind/Resume.c				\
 	unwind/Resume_or_Rethrow.c unwind/SetGR.c unwind/SetIP.c
+endif
 
 # List of arch-independent files needed by local-only library (libunwind):
 libunwind_la_SOURCES_local_nounwind =					\