third_party/mesa: turn off ubsan_vptr, since it's compiled without rtti.

build/config/sanitizers/BUILD.gn

Index: build/config/sanitizers/BUILD.gn
diff --git a/build/config/sanitizers/BUILD.gn b/build/config/sanitizers/BUILD.gn
index e7e36b5db84422529b68fcf56e244ea317fb9490..7e3d11a63ce755c31993f1b63989f75d1e45fe3d 100644
--- a/build/config/sanitizers/BUILD.gn
+++ b/build/config/sanitizers/BUILD.gn
@@ -68,6 +68,18 @@ source_set("options_sources") {
   }
 }
 
+config("ubsan_vptr_flags") {
+  if (is_ubsan_vptr) {

[Dirk Pranke, 2016/04/26 01:00:32]

maybe add a comment here about why this isn't just a part of
:default_sanitizer_flags ,  i.e., mention the usage in //third_party/mesa ?

[krasin, 2016/04/26 03:15:09]

Done.

+    ubsan_vptr_blacklist_path =
+        rebase_path("//tools/ubsan/vptr_blacklist.txt", root_build_dir)
+    cflags = [
+      "-fsanitize=vptr",
+      "-fsanitize-blacklist=$ubsan_vptr_blacklist_path",
+    ]
+    ldflags = [ "-fsanitize=vptr" ]
+  }
+}
+
 # Applies linker flags necessary when either :deps or :default_sanitizer_flags
 # are used.
 config("default_sanitizer_ldflags") {
@@ -93,9 +105,6 @@ config("default_sanitizer_ldflags") {
     if (is_ubsan || is_ubsan_security) {
       ldflags += [ "-fsanitize=undefined" ]
     }
-    if (is_ubsan_vptr) {
-      ldflags += [ "-fsanitize=vptr" ]
-    }
 
     if (is_cfi && !is_nacl) {
       ldflags += [
@@ -245,14 +254,6 @@ config("default_sanitizer_flags") {
       ]
     }
   }
-  if (is_ubsan_vptr) {
-    ubsan_vptr_blacklist_path =
-        rebase_path("//tools/ubsan/vptr_blacklist.txt", root_build_dir)
-    cflags += [
-      "-fsanitize=vptr",
-      "-fsanitize-blacklist=$ubsan_vptr_blacklist_path",
-    ]
-  }
   if (is_ubsan_security) {
     ubsan_blacklist_path =
         rebase_path("//tools/ubsan/blacklist.txt", root_build_dir)