Add OpenMP support

third_party/libunwind/BUILD.mk

@@ -68,8 +68,16 @@ $(THIRD_PARTY_LIBUNWIND_A).pkg:						\
 		$(THIRD_PARTY_LIBUNWIND_A_OBJS)				\
 		$(foreach x,$(THIRD_PARTY_LIBUNWIND_A_DIRECTDEPS),$($(x)_A).pkg)
 
+$(THIRD_PARTY_LIBUNWIND_A_OBJS): private				\
+		CFLAGS +=						\
+			-fno-sanitize=all				\
+			-ffunction-sections				\
+			-fdata-sections					\
+			-D_LIBUNWIND_USE_DLADDR=0
+
 $(THIRD_PARTY_LIBUNWIND_A_OBJS): private				\
 		CXXFLAGS +=						\
+			-fno-sanitize=all				\
 			-ffunction-sections				\
 			-fdata-sections					\
 			-D_LIBUNWIND_USE_DLADDR=0

third_party/libunwind/README.cosmo

@@ -15,5 +15,3 @@ LOCAL CHANGES
 
   - Fixed `_Unwind_FunctionContext` struct to be ABI-compatible with
     code generated by GCC.
-
-  - Added `dontasan` annotations to functions that raised ASAN errors.

third_party/libunwind/Unwind-sjlj.c

@@ -105,7 +105,7 @@ __Unwind_SjLj_SetTopOfFunctionStack(struct _Unwind_FunctionContext *fc) {
 
 
 /// Called at start of each function that catches exceptions
-_LIBUNWIND_EXPORT void dontasan
+_LIBUNWIND_EXPORT void
 _Unwind_SjLj_Register(struct _Unwind_FunctionContext *fc) {
   fc->prev = __Unwind_SjLj_GetTopOfFunctionStack();
   __Unwind_SjLj_SetTopOfFunctionStack(fc);
@@ -113,7 +113,7 @@ _Unwind_SjLj_Register(struct _Unwind_FunctionContext *fc) {
 
 
 /// Called at end of each function that catches exceptions
-_LIBUNWIND_EXPORT void dontasan
+_LIBUNWIND_EXPORT void
 _Unwind_SjLj_Unregister(struct _Unwind_FunctionContext *fc) {
   __Unwind_SjLj_SetTopOfFunctionStack(fc->prev);
 }
@@ -426,7 +426,6 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetGR(struct _Unwind_Context *context,
 
 
 /// Called by personality handler during phase 2 to alter register values.
-dontasan
 _LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
                                      uintptr_t new_value) {
   _LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, reg=%d, value=0x%" PRIuPTR