Add missing unwind code to cxx lib

This patch adds support for the '_Unwind_Complete()' and
'_Unwind_DeleteException()' functions in the cxx lib.

Fixes #275.

base/lib/import/import-stdcxx.mk

@@ -15,6 +15,9 @@ INC_DIR += $(shell echo "int main() {return 0;}" |\
                    sed '/^\#include <\.\.\.> search starts here:/,/^End of search list/!d' |\
                    grep "c++")
 
+# avoid multiple definition of type _mbstate_t
+CC_CXX_OPT += -D_GLIBCXX_HAVE_MBSTATE_T
+
 #
 # Link libstdc++ that comes with the tool chain
 #

base/lib/mk/cxx.mk

@@ -15,7 +15,7 @@ LIBC_SYMBOLS += malloc free calloc realloc \
 #
 # Symbols we wrap (see unwind.cc)
 #
-EH_SYMBOLS = _Unwind_Resume
+EH_SYMBOLS = _Unwind_Resume _Unwind_Complete _Unwind_DeleteException
 
 #
 # Additional functions for ARM

base/src/base/cxx/unwind.cc

@@ -27,9 +27,13 @@ extern "C" {
 
 	/* Unwind function found in all binaries */
 	void  _cxx__Unwind_Resume(void *exc)  __attribute__((weak));
-	void __cxx__Unwind_Resume(void *exc) { 
+	void __cxx__Unwind_Resume(void *exc) {
 		_cxx__Unwind_Resume(exc); }
 
+	void  _cxx__Unwind_DeleteException(void *exc)  __attribute__((weak));
+	void __cxx__Unwind_DeleteException(void *exc) {
+		_cxx__Unwind_DeleteException(exc); }
+
 	/* Special ARM-EABI personality functions */
 #ifdef __ARM_EABI__
 
@@ -41,5 +45,9 @@ extern "C" {
 	int __cxx___aeabi_unwind_cpp_pr1(int state, void *block, void *context) {
 		return _cxx___aeabi_unwind_cpp_pr1(state, block, context); }
 
+	/* Unwind functions found in some binaries */
+	void  _cxx__Unwind_Complete(void *exc)  __attribute__((weak));
+	void __cxx__Unwind_Complete(void *exc) {
+		_cxx__Unwind_Complete(exc); }
 #endif
 }

os/src/lib/ldso/symbol.map

@@ -54,6 +54,8 @@
 
 		/* x86 */
 		__cxa*;
+		_Unwind_Complete;
+		_Unwind_DeleteException;
 		_Unwind_Resume;
 		__gxx_personality_v0;