Add -fno-sanitize-recover=all with sanitizers

By default, UBSan just prints a message but doesn't cause an error exit.
This is not what we want for CI, so adding an extra option to make these
errors fatal in order for CI issues to be obvious.

Makefile

@@ -256,8 +256,9 @@ CXXFLAGS += -ffast-math
 LDFLAGS += $(PROFILE)
 
 ifneq ($(SANITIZE),)
-  CXXFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=all
-  LDFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=all
+  SANITIZE_FLAGS := -fsanitize=$(SANITIZE) -fno-sanitize-recover=all
+  CXXFLAGS += $(SANITIZE_FLAGS)
+  LDFLAGS += $(SANITIZE_FLAGS)
 endif
 
 # enable optimizations. slow to build